Objects: simplify TombstoneMergingKvIterator

Objects: cache peeked key in LmdbKvIterator
Dhfs-app: lazyfs crash test
2025-10-29 04:57:48 +01:00 · 2025-04-22 23:53:41 +02:00 · 2025-04-22 23:53:18 +02:00 · 2025-04-22 23:25:26 +02:00 · 2025-04-22 21:38:15 +02:00 · 2025-04-22 21:37:51 +02:00
86 changed files with 1173 additions and 1398 deletions
--- a/.github/workflows/server.yml
+++ b/.github/workflows/server.yml
@@ -20,26 +20,21 @@ jobs:
    steps:
      - name: Checkout
        uses: actions/checkout@v4
+        with:
+          submodules: 'recursive'

      - name: Install sudo for ACT
        run: apt-get update && apt-get install -y sudo
        if: env.ACT=='true'

-      - name: Install fuse and maven
-        run: sudo apt-get update && sudo apt-get install -y libfuse2
+      - name: Install FUSE
+        run: sudo apt-get update && sudo apt-get install -y libfuse2 libfuse3-dev libfuse3-3 fuse3

-      - name: Download maven
-        run: |
-          cd "$HOME"
-          mkdir maven-bin
-          curl -s -L https://dlcdn.apache.org/maven/maven-3/3.9.9/binaries/apache-maven-3.9.9-bin.tar.gz | tar xvz --strip-components=1 -C maven-bin
-          echo "$HOME"/maven-bin/bin >> $GITHUB_PATH
-
-      - name: Maven info
-        run: |
-          echo $GITHUB_PATH
-          echo $PATH
-          mvn -v
+      - name: User allow other for fuse
+        run: echo "user_allow_other" | sudo tee -a /etc/fuse.conf
+      
+      - name: Dump fuse.conf
+        run: cat /etc/fuse.conf

      - name: Set up JDK 21
        uses: actions/setup-java@v4
@@ -48,6 +43,9 @@ jobs:
          distribution: "zulu"
          cache: maven

+      - name: Build LazyFS
+        run: cd thirdparty/lazyfs/ && ./build.sh
+
      - name: Test with Maven
        run: cd dhfs-parent && mvn -T $(nproc) --batch-mode --update-snapshots package verify

@@ -89,102 +87,6 @@ jobs:
          name: Webui
          path: webui/dist

-  build-native-libs:
-    strategy:
-      matrix:
-        include:
-          - os: ubuntu-latest
-            cross: "linux/amd64"
-          - os: ubuntu-latest
-            cross: "linux/arm64"
-          - os: macos-latest
-
-    runs-on: ${{ matrix.os }}
-    env:
-      DO_LOCAL_BUILD: ${{ matrix.os == 'macos-latest' }}
-      DOCKER_PLATFORM: ${{ matrix.cross || 'NATIVE' }}
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Set SANITIZED_DOCKER_PLATFORM
-        run: echo "SANITIZED_DOCKER_PLATFORM=$(echo $DOCKER_PLATFORM | tr / _ )" >> $GITHUB_ENV
-
-      - name: Set DOCKER_BUILDER_IMAGE
-        run: echo "DOCKER_BUILDER_IMAGE=dhfs_lib_builder-${{matrix.os}}-$SANITIZED_DOCKER_PLATFORM" >> $GITHUB_ENV
-
-      - name: Build config
-        run: |
-          echo DO_LOCAL_BUILD: $DO_LOCAL_BUILD
-          echo DOCKER_PLATFORM: $DOCKER_PLATFORM
-          echo SANITIZED_DOCKER_PLATFORM: $SANITIZED_DOCKER_PLATFORM
-          echo DOCKER_BUILDER_IMAGE: $DOCKER_BUILDER_IMAGE
-
-      - name: Set up JDK 21
-        if: ${{ env.DO_LOCAL_BUILD == 'TRUE' }}
-        uses: actions/setup-java@v4
-        with:
-          java-version: "21"
-          distribution: "zulu"
-          cache: maven
-
-      - name: Set up Docker Buildx
-        if: ${{ env.DO_LOCAL_BUILD != 'TRUE' }}
-        uses: docker/setup-buildx-action@v3
-
-      - name: Set up QEMU
-        if: ${{ env.DO_LOCAL_BUILD != 'TRUE' }}
-        uses: docker/setup-qemu-action@v3
-
-      - name: Build Docker builder image
-        if: ${{ env.DO_LOCAL_BUILD != 'TRUE' }}
-        uses: docker/build-push-action@v5
-        with:
-          context: ./libdhfs_support/builder
-          file: ./libdhfs_support/builder/Dockerfile
-          push: false
-          platforms: ${{ env.DOCKER_PLATFORM }}
-          tags: ${{ env.DOCKER_BUILDER_IMAGE }}
-          cache-from: type=gha,scope=build-${{ env.DOCKER_BUILDER_IMAGE }}
-          cache-to: type=gha,mode=max,scope=build-${{ env.DOCKER_BUILDER_IMAGE }}
-          load: true
-
-      - name: Build the library
-        run: |
-          CMAKE_ARGS="-DCMAKE_BUILD_TYPE=Release" libdhfs_support/builder/cross-build.sh both build "$(pwd)/result"
-
-      - name: Upload build
-        uses: actions/upload-artifact@v4
-        with:
-          name: NativeLib-${{ matrix.os }}-${{ env.SANITIZED_DOCKER_PLATFORM }}
-          path: result
-
-  merge-native-libs:
-    runs-on: ubuntu-latest
-    needs: [build-native-libs]
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Download artifacts
-        uses: actions/download-artifact@v4
-        with:
-          path: downloaded-libs
-
-      - name: Merge all
-        run: rsync -av downloaded-libs/NativeLib*/* result/
-
-      - name: Check that libs exists
-        run: |
-          test -f "result/Linux-x86_64/libdhfs_support.so" || exit 1
-
-      - name: Upload
-        uses: actions/upload-artifact@v4
-        with:
-          name: NativeLibs
-          path: result
-
  publish-docker:
    runs-on: ubuntu-latest
    permissions:
@@ -194,7 +96,7 @@ jobs:
      # with sigstore/fulcio when running outside of PRs.
      id-token: write

-    needs: [build-webui, merge-native-libs, build-dhfs]
+    needs: [build-webui, build-dhfs]

    steps:
      - name: Checkout repository
@@ -212,12 +114,6 @@ jobs:
          name: Webui
          path: webui-dist-downloaded

-      - name: Download native libs
-        uses: actions/download-artifact@v4
-        with:
-          name: NativeLibs
-          path: dhfs-native-downloaded
-
      - name: Show all the files
        run: find .

@@ -293,7 +189,7 @@ jobs:
      # with sigstore/fulcio when running outside of PRs.
      id-token: write

-    needs: [build-webui, merge-native-libs, build-dhfs]
+    needs: [build-webui, build-dhfs]

    steps:
      - name: Checkout repository
@@ -309,11 +205,6 @@ jobs:
          name: Webui
          path: webui-dist-downloaded

-      - uses: actions/download-artifact@v4
-        with:
-          name: NativeLibs
-          path: dhfs-native-downloaded
-
      - name: Show all the files
        run: find .

@@ -326,9 +217,6 @@ jobs:
      - name: Copy Webui
        run: cp -r ./webui-dist-downloaded "run-wrapper-out/dhfs/app/Webui"

-      - name: Copy Webui
-        run: cp -r ./dhfs-native-downloaded "run-wrapper-out/dhfs/app/NativeLibs"
-
      - name: Copy run wrapper
        run: cp -r ./run-wrapper/* "run-wrapper-out/dhfs/app/"

--- a/.gitmodules
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "thirdparty/lazyfs/lazyfs"]
+	path = thirdparty/lazyfs/lazyfs
+	url = git@github.com:dsrhaslab/lazyfs.git
--- a/Dockerfile.ci
+++ b/Dockerfile.ci
@@ -9,8 +9,6 @@ COPY ./dhfs-package-downloaded/*.jar .
 COPY ./dhfs-package-downloaded/app .
 COPY ./dhfs-package-downloaded/quarkus .

-WORKDIR /usr/src/app/native-libs
-COPY ./dhfs-native-downloaded/. .
 WORKDIR /usr/src/app/webui
 COPY ./webui-dist-downloaded/. .

--- a/dhfs-parent/.run/Main
+++ b/dhfs-parent/.run/Main
@@ -2,7 +2,7 @@
  <configuration default="false" name="Main 2" type="QsApplicationConfigurationType" factoryName="QuarkusApplication">
    <option name="MAIN_CLASS_NAME" value="com.usatiuk.dhfs.app.Main" />
    <module name="dhfs-app" />
-    <option name="VM_PARAMETERS" value="-XX:+UnlockDiagnosticVMOptions -XX:+DebugNonSafepoints --add-exports java.base/sun.nio.ch=ALL-UNNAMED --add-opens=java.base/java.nio=ALL-UNNAMED --add-exports java.base/jdk.internal.access=ALL-UNNAMED -ea -Dcom.usatiuk.dhfs.supportlib.native-path=$ProjectFileDir$/target/classes/native -Xmx2G -Ddhfs.webui.root=$ProjectFileDir$/../webui/dist -Ddhfs.fuse.root=${HOME}/dhfs_test/2/fuse -Ddhfs.objects.persistence.files.root=${HOME}/dhfs_test/2/data -Ddhfs.objects.persistence.stuff.root=${HOME}/dhfs_test/2/data/stuff -Ddhfs.objects.peerdiscovery.broadcast=false -Dquarkus.http.port=9020 -Dquarkus.http.ssl-port=9021 -Ddhfs.peerdiscovery.preset-uuid=22000000-0000-0000-0000-000000000000 -Ddhfs.peerdiscovery.static-peers=11000000-0000-0000-0000-000000000000:127.0.0.1:9010:9011" />
+    <option name="VM_PARAMETERS" value="-XX:+UnlockDiagnosticVMOptions -XX:+DebugNonSafepoints --add-exports java.base/sun.nio.ch=ALL-UNNAMED --add-opens=java.base/java.nio=ALL-UNNAMED --add-exports java.base/jdk.internal.access=ALL-UNNAMED -ea -Xmx2G -Ddhfs.webui.root=$ProjectFileDir$/../webui/dist -Ddhfs.fuse.root=${HOME}/dhfs_test/2/fuse -Ddhfs.objects.persistence.files.root=${HOME}/dhfs_test/2/data -Ddhfs.objects.persistence.stuff.root=${HOME}/dhfs_test/2/data/stuff -Ddhfs.objects.peerdiscovery.broadcast=false -Dquarkus.http.port=9020 -Dquarkus.http.ssl-port=9021 -Ddhfs.peerdiscovery.preset-uuid=22000000-0000-0000-0000-000000000000 -Ddhfs.peerdiscovery.static-peers=11000000-0000-0000-0000-000000000000:127.0.0.1:8080:9011" />
    <extension name="coverage">
      <pattern>
        <option name="PATTERN" value="com.usatiuk.dhfs.*" />
--- a/dhfs-parent/.run/Main.run.xml
+++ b/dhfs-parent/.run/Main.run.xml
@@ -2,7 +2,7 @@
  <configuration default="false" name="Main" type="QsApplicationConfigurationType" factoryName="QuarkusApplication" nameIsGenerated="true">
    <option name="MAIN_CLASS_NAME" value="com.usatiuk.dhfs.app.Main" />
    <module name="dhfs-app" />
-    <option name="VM_PARAMETERS" value="-XX:+UnlockDiagnosticVMOptions -XX:+DebugNonSafepoints --add-exports java.base/sun.nio.ch=ALL-UNNAMED --add-opens=java.base/java.nio=ALL-UNNAMED --add-exports java.base/jdk.internal.access=ALL-UNNAMED -ea -Dcom.usatiuk.dhfs.supportlib.native-path=$ProjectFileDir$/target/classes/native -Xmx2G -Ddhfs.webui.root=$ProjectFileDir$/../webui/dist -Ddhfs.fuse.root=${HOME}/dhfs_test/1/fuse -Ddhfs.objects.persistence.files.root=${HOME}/dhfs_test/1/data -Ddhfs.objects.persistence.stuff.root=${HOME}/dhfs_test/1/data/stuff -Ddhfs.objects.peerdiscovery.broadcast=true -Dquarkus.http.port=8080 -Dquarkus.http.ssl-port=9011 -Ddhfs.peerdiscovery.preset-uuid=11000000-0000-0000-0000-000000000000 -Ddhfs.peerdiscovery.static-peers=22000000-0000-0000-0000-000000000000:127.0.0.1:9020:9021 -Dquarkus.http.host=0.0.0.0" />
+    <option name="VM_PARAMETERS" value="-XX:+UnlockDiagnosticVMOptions --enable-preview -XX:+UseParallelGC -XX:+DebugNonSafepoints --add-exports java.base/sun.nio.ch=ALL-UNNAMED --add-opens=java.base/java.nio=ALL-UNNAMED --add-exports java.base/jdk.internal.access=ALL-UNNAMED -ea -Xmx2G -Ddhfs.webui.root=$ProjectFileDir$/../webui/dist -Ddhfs.fuse.root=${HOME}/dhfs_test/1/fuse -Ddhfs.objects.persistence.files.root=${HOME}/dhfs_test/1/data -Ddhfs.objects.persistence.stuff.root=${HOME}/dhfs_test/1/data/stuff -Ddhfs.objects.peerdiscovery.broadcast=true -Dquarkus.http.port=8080 -Dquarkus.http.ssl-port=9011 -Ddhfs.peerdiscovery.preset-uuid=11000000-0000-0000-0000-000000000000 -Ddhfs.peerdiscovery.static-peers=22000000-0000-0000-0000-000000000000:127.0.0.1:9020:9021 -Dquarkus.http.host=0.0.0.0" />
    <extension name="coverage">
      <pattern>
        <option name="PATTERN" value="com.usatiuk.dhfs.*" />
--- a/dhfs-parent/dhfs-app/pom.xml
+++ b/dhfs-parent/dhfs-app/pom.xml
@@ -72,26 +72,6 @@
            <artifactId>quarkus-junit5</artifactId>
            <scope>test</scope>
        </dependency>
-        <dependency>
-            <groupId>com.github.SerCeMan</groupId>
-            <artifactId>jnr-fuse</artifactId>
-            <version>44ed40f8ce</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-ffi</artifactId>
-            <version>2.2.16</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-posix</artifactId>
-            <version>3.1.19</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-constants</artifactId>
-            <version>0.10.4</version>
-        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
@@ -127,11 +107,6 @@
            <artifactId>kleppmanntree</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
-        <dependency>
-            <groupId>com.usatiuk.dhfs</groupId>
-            <artifactId>supportlib</artifactId>
-            <version>1.0-SNAPSHOT</version>
-        </dependency>
        <dependency>
            <groupId>com.usatiuk.dhfs</groupId>
            <artifactId>objects</artifactId>
--- a/dhfs-parent/dhfs-app/src/test/java/com/usatiuk/dhfs/integration/DhfsFusex3IT.java
+++ b/dhfs-parent/dhfs-app/src/test/java/com/usatiuk/dhfs/integration/DhfsFusex3IT.java
@@ -35,13 +35,15 @@ public class DhfsFusex3IT {
    String c2uuid;
    String c3uuid;

+    Network network;
+
    // This calculation is somewhat racy, so keep it hardcoded for now
    long emptyFileCount = 9;

    @BeforeEach
    void setup(TestInfo testInfo) throws IOException, InterruptedException, TimeoutException {
        // TODO: Dedup
-        Network network = Network.newNetwork();
+        network = Network.newNetwork();

        container1 = new GenericContainer<>(DhfsImage.getInstance())
                .withPrivilegedMode(true)
@@ -252,21 +254,22 @@ public class DhfsFusex3IT {
        await().atMost(45, TimeUnit.SECONDS).until(() -> "tesempty\n".equals(container3.execInContainer("/bin/sh", "-c", "cat /dhfs_test/fuse/testf").getStdout()));

        var client = DockerClientFactory.instance().client();
-        client.pauseContainerCmd(container1.getContainerId()).exec();
-        client.pauseContainerCmd(container2.getContainerId()).exec();
-        // Pauses needed as otherwise docker buffers some incoming packets
+        client.disconnectFromNetworkCmd().withContainerId(container1.getContainerId()).withNetworkId(network.getId()).exec();
+        client.disconnectFromNetworkCmd().withContainerId(container2.getContainerId()).withNetworkId(network.getId()).exec();
+        client.disconnectFromNetworkCmd().withContainerId(container3.getContainerId()).withNetworkId(network.getId()).exec();
+
        waitingConsumer3.waitUntil(frame -> frame.getUtf8String().contains("Lost connection to"), 60, TimeUnit.SECONDS, 2);
-        await().atMost(45, TimeUnit.SECONDS).until(() -> 0 == container3.execInContainer("/bin/sh", "-c", "echo test3 >> /dhfs_test/fuse/testf").getExitCode());
-        client.pauseContainerCmd(container3.getContainerId()).exec();
-        client.unpauseContainerCmd(container2.getContainerId()).exec();
        waitingConsumer2.waitUntil(frame -> frame.getUtf8String().contains("Lost connection to"), 60, TimeUnit.SECONDS, 2);
-        await().atMost(45, TimeUnit.SECONDS).until(() -> 0 == container2.execInContainer("/bin/sh", "-c", "echo test2 >> /dhfs_test/fuse/testf").getExitCode());
-        client.pauseContainerCmd(container2.getContainerId()).exec();
-        client.unpauseContainerCmd(container1.getContainerId()).exec();
        waitingConsumer1.waitUntil(frame -> frame.getUtf8String().contains("Lost connection to"), 60, TimeUnit.SECONDS, 2);
+
+        await().atMost(45, TimeUnit.SECONDS).until(() -> 0 == container3.execInContainer("/bin/sh", "-c", "echo test3 >> /dhfs_test/fuse/testf").getExitCode());
+        await().atMost(45, TimeUnit.SECONDS).until(() -> 0 == container2.execInContainer("/bin/sh", "-c", "echo test2 >> /dhfs_test/fuse/testf").getExitCode());
        await().atMost(45, TimeUnit.SECONDS).until(() -> 0 == container1.execInContainer("/bin/sh", "-c", "echo test1 >> /dhfs_test/fuse/testf").getExitCode());
-        client.unpauseContainerCmd(container2.getContainerId()).exec();
-        client.unpauseContainerCmd(container3.getContainerId()).exec();
+
+        client.connectToNetworkCmd().withContainerId(container1.getContainerId()).withNetworkId(network.getId()).exec();
+        client.connectToNetworkCmd().withContainerId(container2.getContainerId()).withNetworkId(network.getId()).exec();
+        client.connectToNetworkCmd().withContainerId(container3.getContainerId()).withNetworkId(network.getId()).exec();
+
        Log.warn("Waiting for connections");
        waitingConsumer1.waitUntil(frame -> frame.getUtf8String().contains("Connected"), 60, TimeUnit.SECONDS, 2);
        waitingConsumer2.waitUntil(frame -> frame.getUtf8String().contains("Connected"), 60, TimeUnit.SECONDS, 2);
--- a/dhfs-parent/dhfs-app/src/test/java/com/usatiuk/dhfs/integration/DhfsImage.java
+++ b/dhfs-parent/dhfs-app/src/test/java/com/usatiuk/dhfs/integration/DhfsImage.java
@@ -79,7 +79,6 @@ public class DhfsImage implements Future<String> {
                                        "-Ddhfs.objects.sync.timeout=10",
                                        "-Ddhfs.objects.sync.ping.timeout=5",
                                        "-Ddhfs.objects.reconnect_interval=1s",
-                                        "-Dcom.usatiuk.dhfs.supportlib.native-path=/libs",
                                        "-Dquarkus.log.category.\"com.usatiuk\".level=TRACE",
                                        "-Dquarkus.log.category.\"com.usatiuk.dhfs\".level=TRACE",
                                        "-Ddhfs.objects.periodic-push-op-interval=5s",
--- a/dhfs-parent/dhfs-app/src/test/java/com/usatiuk/dhfs/integration/LazyFs.java
+++ b/dhfs-parent/dhfs-app/src/test/java/com/usatiuk/dhfs/integration/LazyFs.java
@@ -0,0 +1,177 @@
+package com.usatiuk.dhfs.integration;
+
+import io.quarkus.logging.Log;
+
+import java.io.*;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.concurrent.ThreadLocalRandom;
+import java.util.concurrent.TimeUnit;
+
+public class LazyFs {
+    private static final String lazyFsPath;
+
+    private final String dataRoot;
+    private final String lazyFsDataPath;
+    private final String name;
+    private final File tmpConfigFile;
+    private final File fifoPath;
+
+    static {
+        lazyFsPath = System.getProperty("lazyFsPath");
+        System.out.println("LazyFs Path: " + lazyFsPath);
+    }
+
+    public LazyFs(String name, String dataRoot, String lazyFsDataPath) {
+        this.name = name;
+        this.dataRoot = dataRoot;
+        this.lazyFsDataPath = lazyFsDataPath;
+
+        try {
+            tmpConfigFile = File.createTempFile("lazyfs", ".conf");
+            tmpConfigFile.deleteOnExit();
+
+            fifoPath = new File("/tmp/" + ThreadLocalRandom.current().nextLong() + ".faultsfifo");
+            fifoPath.deleteOnExit();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private Thread outputPiper;
+    private Process fs;
+
+    private String fifoPath() {
+        return fifoPath.getAbsolutePath();
+    }
+
+    public void start() {
+        var lfsPath = Path.of(lazyFsPath).resolve("build").resolve("lazyfs");
+        if (!lfsPath.toFile().isFile())
+            throw new IllegalStateException("LazyFs binary does not exist: " + lfsPath.toAbsolutePath());
+        if (!lfsPath.toFile().canExecute())
+            throw new IllegalStateException("LazyFs binary is not executable: " + lfsPath.toAbsolutePath());
+
+        try (var rwFile = new RandomAccessFile(tmpConfigFile, "rw");
+             var channel = rwFile.getChannel()) {
+            channel.truncate(0);
+            var config = "[faults]\n" +
+                    "fifo_path=\"" + fifoPath() + "\"\n" +
+                    "[cache]\n" +
+                    "apply_eviction=false\n" +
+                    "[cache.simple]\n" +
+                    "custom_size=\"1gb\"\n" +
+                    "blocks_per_page=1\n" +
+                    "[filesystem]\n" +
+                    "log_all_operations=false\n" +
+                    "logfile=\"\"";
+            rwFile.write(config.getBytes());
+            Log.info("LazyFs config: \n" + config);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+
+        var argList = new ArrayList<String>();
+
+        argList.add(lfsPath.toString());
+        argList.add(Path.of(dataRoot).toString());
+        argList.add("--config-path");
+        argList.add(tmpConfigFile.getAbsolutePath());
+        argList.add("-o");
+        argList.add("allow_other");
+        argList.add("-o");
+        argList.add("modules=subdir");
+        argList.add("-o");
+        argList.add("subdir=" + Path.of(lazyFsDataPath).toAbsolutePath().toString());
+        try {
+            Log.info("Starting LazyFs " + argList);
+            fs = Runtime.getRuntime().exec(argList.toArray(String[]::new));
+            Thread.sleep(1000);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+
+        outputPiper = new Thread(() -> {
+            try {
+                try (BufferedReader input = new BufferedReader(new InputStreamReader(fs.getInputStream()))) {
+                    String line;
+
+                    while ((line = input.readLine()) != null) {
+                        System.out.println(line);
+                    }
+                }
+            } catch (Exception e) {
+                Log.info("Exception in LazyFs piper", e);
+            }
+        });
+        outputPiper.start();
+        outputPiper = new Thread(() -> {
+            try {
+                try (BufferedReader input = new BufferedReader(new InputStreamReader(fs.getErrorStream()))) {
+                    String line;
+
+                    while ((line = input.readLine()) != null) {
+                        System.out.println(line);
+                    }
+                }
+            } catch (Exception e) {
+                Log.info("Exception in LazyFs piper", e);
+            }
+        });
+        outputPiper.start();
+    }
+
+    public void crash() {
+        try {
+            var cmd = "echo \"lazyfs::crash::timing=after::op=write::from_rgx=*\" > " + fifoPath();
+            System.out.println("Running command: " + cmd);
+            Runtime.getRuntime().exec(new String[]{"/bin/sh", "-c", cmd});
+            stop();
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public void stop() {
+        try {
+            if (fs == null) {
+                return;
+            }
+            Runtime.getRuntime().exec(new String[]{"/bin/sh", "-c", "fusermount3 -u " + dataRoot});
+            if (!fs.waitFor(1, TimeUnit.SECONDS))
+                throw new RuntimeException("LazyFs process did not stop in time");
+            fs = null;
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+//    Doesn't actually work?
+//
+//    public void crashop() {
+//        try {
+//            var cmd = "echo \"lazyfs::torn-op::file=" + Path.of(lazyFsDataPath).toAbsolutePath().toString() + "/objects/data.mdb::persist=1,3::parts=3::occurrence=5\" > /tmp/faults.fifo";
+//            System.out.println("Running command: " + cmd);
+//            Runtime.getRuntime().exec(new String[]{"/bin/sh", "-c", cmd});
+//            Thread.sleep(1000);
+//            Runtime.getRuntime().exec(new String[]{"/bin/sh", "-c", "fusermount3 -u " + dataRoot});
+//            Thread.sleep(1000);
+//        } catch (Exception e) {
+//            throw new RuntimeException(e);
+//        }
+//    }
+//
+//    public void crashseq() {
+//        try {
+//            var cmd = "echo \"lazyfs::torn-seq::op=write::file=" + Path.of(lazyFsDataPath).toAbsolutePath().toString() + "/objects/data.mdb::persist=1,4::occurrence=2\" > /tmp/faults.fifo";
+//            System.out.println("Running command: " + cmd);
+//            Runtime.getRuntime().exec(new String[]{"/bin/sh", "-c", cmd});
+//            Thread.sleep(1000);
+//            Runtime.getRuntime().exec(new String[]{"/bin/sh", "-c", "fusermount3 -u " + dataRoot});
+//            Thread.sleep(1000);
+//        } catch (Exception e) {
+//            throw new RuntimeException(e);
+//        }
+//    }
+}
+
--- a/dhfs-parent/dhfs-app/src/test/java/com/usatiuk/dhfs/integration/LazyFsIT.java
+++ b/dhfs-parent/dhfs-app/src/test/java/com/usatiuk/dhfs/integration/LazyFsIT.java
@@ -0,0 +1,199 @@
+package com.usatiuk.dhfs.integration;
+
+import com.github.dockerjava.api.model.Device;
+import com.usatiuk.dhfs.TestDataCleaner;
+import io.quarkus.logging.Log;
+import org.junit.jupiter.api.*;
+import org.slf4j.LoggerFactory;
+import org.testcontainers.DockerClientFactory;
+import org.testcontainers.containers.GenericContainer;
+import org.testcontainers.containers.Network;
+import org.testcontainers.containers.output.Slf4jLogConsumer;
+import org.testcontainers.containers.output.WaitingConsumer;
+import org.testcontainers.containers.wait.strategy.Wait;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.time.Duration;
+import java.util.Objects;
+import java.util.UUID;
+import java.util.concurrent.CyclicBarrier;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+import java.util.stream.Stream;
+
+import static org.awaitility.Awaitility.await;
+
+public class LazyFsIT {
+    GenericContainer<?> container1;
+    GenericContainer<?> container2;
+
+    WaitingConsumer waitingConsumer1;
+    WaitingConsumer waitingConsumer2;
+
+    String c1uuid;
+    String c2uuid;
+
+    File data1;
+    File data2;
+    File data1Lazy;
+
+    LazyFs lazyFs1;
+
+    @BeforeEach
+    void setup(TestInfo testInfo) throws IOException, InterruptedException, TimeoutException {
+        data1 = Files.createTempDirectory("dhfsdata").toFile();
+        data2 = Files.createTempDirectory("dhfsdata").toFile();
+        data1Lazy = Files.createTempDirectory("lazyfsroot").toFile();
+
+        Network network = Network.newNetwork();
+
+        lazyFs1 = new LazyFs(testInfo.getDisplayName(), data1.toString(), data1Lazy.toString());
+        lazyFs1.start();
+
+        container1 = new GenericContainer<>(DhfsImage.getInstance())
+                .withPrivilegedMode(true)
+                .withCreateContainerCmdModifier(cmd -> Objects.requireNonNull(cmd.getHostConfig()).withDevices(Device.parse("/dev/fuse")))
+                .waitingFor(Wait.forLogMessage(".*Listening.*", 1).withStartupTimeout(Duration.ofSeconds(60))).withNetwork(network)
+                .withFileSystemBind(data1.getAbsolutePath(), "/dhfs_test/data");
+        container2 = new GenericContainer<>(DhfsImage.getInstance())
+                .withPrivilegedMode(true)
+                .withCreateContainerCmdModifier(cmd -> Objects.requireNonNull(cmd.getHostConfig()).withDevices(Device.parse("/dev/fuse")))
+                .waitingFor(Wait.forLogMessage(".*Listening.*", 1).withStartupTimeout(Duration.ofSeconds(60))).withNetwork(network)
+                .withFileSystemBind(data2.getAbsolutePath(), "/dhfs_test/data");
+
+        Stream.of(container1, container2).parallel().forEach(GenericContainer::start);
+
+        waitingConsumer1 = new WaitingConsumer();
+        var loggingConsumer1 = new Slf4jLogConsumer(LoggerFactory.getLogger(LazyFsIT.class)).withPrefix("1-" + testInfo.getDisplayName());
+        container1.followOutput(loggingConsumer1.andThen(waitingConsumer1));
+        waitingConsumer2 = new WaitingConsumer();
+        var loggingConsumer2 = new Slf4jLogConsumer(LoggerFactory.getLogger(LazyFsIT.class)).withPrefix("2-" + testInfo.getDisplayName());
+        container2.followOutput(loggingConsumer2.andThen(waitingConsumer2));
+
+        c1uuid = container1.execInContainer("/bin/sh", "-c", "cat /dhfs_test/data/stuff/self_uuid").getStdout();
+        c2uuid = container2.execInContainer("/bin/sh", "-c", "cat /dhfs_test/data/stuff/self_uuid").getStdout();
+
+        Assertions.assertDoesNotThrow(() -> UUID.fromString(c1uuid));
+        Assertions.assertDoesNotThrow(() -> UUID.fromString(c2uuid));
+
+        waitingConsumer2.waitUntil(frame -> frame.getUtf8String().contains("New address"), 60, TimeUnit.SECONDS);
+        waitingConsumer1.waitUntil(frame -> frame.getUtf8String().contains("New address"), 60, TimeUnit.SECONDS);
+
+        var c1curl = container1.execInContainer("/bin/sh", "-c",
+                "curl --header \"Content-Type: application/json\" " +
+                        "  --request PUT " +
+                        "  --data '{\"uuid\":\"" + c2uuid + "\"}' " +
+                        "  http://localhost:8080/peers-manage/known-peers");
+
+        var c2curl = container2.execInContainer("/bin/sh", "-c",
+                "curl --header \"Content-Type: application/json\" " +
+                        "  --request PUT " +
+                        "  --data '{\"uuid\":\"" + c1uuid + "\"}' " +
+                        "  http://localhost:8080/peers-manage/known-peers");
+
+        waitingConsumer2.waitUntil(frame -> frame.getUtf8String().contains("Connected"), 60, TimeUnit.SECONDS);
+        waitingConsumer1.waitUntil(frame -> frame.getUtf8String().contains("Connected"), 60, TimeUnit.SECONDS);
+    }
+
+    @AfterEach
+    void stop() {
+        lazyFs1.stop();
+
+        Stream.of(container1, container2).parallel().forEach(GenericContainer::stop);
+        TestDataCleaner.purgeDirectory(data1);
+        TestDataCleaner.purgeDirectory(data1Lazy);
+        TestDataCleaner.purgeDirectory(data2);
+    }
+
+    @Test
+    void killTest(TestInfo testInfo) throws Exception {
+        var executor = Executors.newFixedThreadPool(2);
+        var barrier = new CyclicBarrier(2);
+        var ret1 = executor.submit(() -> {
+            try {
+                Log.info("Writing to container 1");
+                barrier.await();
+                container1.execInContainer("/bin/sh", "-c", "counter=0; while true; do counter=`expr $counter + 1`; echo $counter >> /dhfs_test/fuse/test1; done");
+            } catch (Exception e) {
+                throw new RuntimeException(e);
+            }
+        });
+        barrier.await();
+        Thread.sleep(1000);
+        Log.info("Killing");
+        lazyFs1.crash();
+
+        waitingConsumer1.waitUntil(frame -> frame.getUtf8String().contains("Caused by: org.lmdbjava"), 5, TimeUnit.SECONDS);
+        Thread.sleep(1000);
+        var client = DockerClientFactory.instance().client();
+        client.killContainerCmd(container1.getContainerId()).exec();
+        container1.stop();
+        waitingConsumer2.waitUntil(frame -> frame.getUtf8String().contains("Lost connection to"), 60, TimeUnit.SECONDS);
+        Log.info("Restart");
+        lazyFs1.start();
+        container1.start();
+        waitingConsumer1 = new WaitingConsumer();
+        var loggingConsumer1 = new Slf4jLogConsumer(LoggerFactory.getLogger(LazyFsIT.class)).withPrefix("1-" + testInfo.getDisplayName());
+        container1.followOutput(loggingConsumer1.andThen(waitingConsumer1));
+        waitingConsumer2.waitUntil(frame -> frame.getUtf8String().contains("Connected"), 60, TimeUnit.SECONDS);
+        waitingConsumer1.waitUntil(frame -> frame.getUtf8String().contains("Connected"), 60, TimeUnit.SECONDS);
+
+        await().atMost(45, TimeUnit.SECONDS).until(() -> {
+            Log.info("Listing consistency");
+            var ls1 = container1.execInContainer("/bin/sh", "-c", "ls /dhfs_test/fuse");
+            var cat1 = container1.execInContainer("/bin/sh", "-c", "cat /dhfs_test/fuse/*");
+            var ls2 = container2.execInContainer("/bin/sh", "-c", "ls /dhfs_test/fuse");
+            var cat2 = container2.execInContainer("/bin/sh", "-c", "cat /dhfs_test/fuse/*");
+            Log.info(ls1);
+            Log.info(cat1);
+            Log.info(ls2);
+            Log.info(cat2);
+
+            return ls1.equals(ls2) && cat1.equals(cat2);
+        });
+    }
+
+//    @Test
+//    void killTestDirs(TestInfo testInfo) throws Exception {
+//        var executor = Executors.newFixedThreadPool(2);
+//        var barrier = new CyclicBarrier(2);
+//        var ret1 = executor.submit(() -> {
+//            try {
+//                Log.info("Writing to container 1");
+//                barrier.await();
+//                container1.execInContainer("/bin/sh", "-c", "counter=0; while true; do counter=`expr $counter + 1`; echo $counter >> /dhfs_test/fuse/test$counter; done");
+//            } catch (Exception e) {
+//                throw new RuntimeException(e);
+//            }
+//        });
+//        barrier.await();
+//        Thread.sleep(10000);
+//        var client = DockerClientFactory.instance().client();
+//        client.killContainerCmd(container1.getContainerId()).exec();
+//        container1.stop();
+//        waitingConsumer2.waitUntil(frame -> frame.getUtf8String().contains("Lost connection to"), 60, TimeUnit.SECONDS);
+//        container1.start();
+//        waitingConsumer1 = new WaitingConsumer();
+//        var loggingConsumer1 = new Slf4jLogConsumer(LoggerFactory.getLogger(LazyFsIT.class)).withPrefix("1-" + testInfo.getDisplayName());
+//        container1.followOutput(loggingConsumer1.andThen(waitingConsumer1));
+//        waitingConsumer2.waitUntil(frame -> frame.getUtf8String().contains("Connected"), 60, TimeUnit.SECONDS);
+//        waitingConsumer1.waitUntil(frame -> frame.getUtf8String().contains("Connected"), 60, TimeUnit.SECONDS);
+//
+//        await().atMost(45, TimeUnit.SECONDS).until(() -> {
+//            Log.info("Listing consistency");
+//            var ls1 = container1.execInContainer("/bin/sh", "-c", "ls /dhfs_test/fuse");
+//            var cat1 = container1.execInContainer("/bin/sh", "-c", "cat /dhfs_test/fuse/*");
+//            var ls2 = container2.execInContainer("/bin/sh", "-c", "ls /dhfs_test/fuse");
+//            var cat2 = container2.execInContainer("/bin/sh", "-c", "cat /dhfs_test/fuse/*");
+//            Log.info(ls1);
+//            Log.info(cat1);
+//            Log.info(ls2);
+//            Log.info(cat2);
+//
+//            return ls1.equals(ls2) && cat1.equals(cat2);
+//        });
+//    }
+}
--- a/dhfs-parent/dhfs-app/src/test/resources/application.properties
+++ b/dhfs-parent/dhfs-app/src/test/resources/application.properties
@@ -5,7 +5,6 @@ dhfs.objects.ref_verification=true
 dhfs.objects.deletion.delay=0
 quarkus.log.category."com.usatiuk.dhfs".level=TRACE
 quarkus.log.category."com.usatiuk.dhfs".min-level=TRACE
-quarkus.class-loading.parent-first-artifacts=com.usatiuk.dhfs:supportlib
 quarkus.http.test-port=0
 quarkus.http.test-ssl-port=0
 dhfs.local-discovery=false
--- a/dhfs-parent/dhfs-fs/pom.xml
+++ b/dhfs-parent/dhfs-fs/pom.xml
@@ -72,26 +72,6 @@
            <artifactId>quarkus-junit5</artifactId>
            <scope>test</scope>
        </dependency>
-        <dependency>
-            <groupId>com.github.SerCeMan</groupId>
-            <artifactId>jnr-fuse</artifactId>
-            <version>44ed40f8ce</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-ffi</artifactId>
-            <version>2.2.16</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-posix</artifactId>
-            <version>3.1.19</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-constants</artifactId>
-            <version>0.10.4</version>
-        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
@@ -127,11 +107,6 @@
            <artifactId>kleppmanntree</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
-        <dependency>
-            <groupId>com.usatiuk.dhfs</groupId>
-            <artifactId>supportlib</artifactId>
-            <version>1.0-SNAPSHOT</version>
-        </dependency>
        <dependency>
            <groupId>com.usatiuk.dhfs</groupId>
            <artifactId>objects</artifactId>
--- a/dhfs-parent/dhfs-fs/src/main/java/com/usatiuk/dhfs/files/objects/File.java
+++ b/dhfs-parent/dhfs-fs/src/main/java/com/usatiuk/dhfs/files/objects/File.java
@@ -1,10 +1,10 @@
 package com.usatiuk.dhfs.files.objects;

 import com.usatiuk.dhfs.JDataRemote;
-import com.usatiuk.objects.JObjectKey;
 import com.usatiuk.dhfs.jmap.JMapHolder;
 import com.usatiuk.dhfs.jmap.JMapLongKey;
 import com.usatiuk.dhfs.repository.JDataRemoteDto;
+import com.usatiuk.objects.JObjectKey;

 import java.util.Collection;
 import java.util.Set;
@@ -28,6 +28,10 @@ public record File(JObjectKey key, long mode, long cTime, long mTime,
        return new File(key, mode, cTime, mTime, symlink);
    }

+    public File withCurrentMTime() {
+        return new File(key, mode, cTime, System.currentTimeMillis(), symlink);
+    }
+
    @Override
    public Collection<JObjectKey> collectRefsTo() {
        return Set.of();
--- a/dhfs-parent/dhfs-fs/src/main/java/com/usatiuk/dhfs/files/service/DhfsFileServiceImpl.java
+++ b/dhfs-parent/dhfs-fs/src/main/java/com/usatiuk/dhfs/files/service/DhfsFileServiceImpl.java
@@ -33,6 +33,7 @@ import jakarta.inject.Inject;
 import org.apache.commons.lang3.tuple.Pair;
 import org.eclipse.microprofile.config.inject.ConfigProperty;

+import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
 import java.util.*;
@@ -246,7 +247,7 @@ public class DhfsFileServiceImpl implements DhfsFileService {
            } else if (dent instanceof RemoteObjectMeta) {
                var remote = remoteTx.getData(JDataRemote.class, uuid).orElse(null);
                if (remote instanceof File f) {
-                    remoteTx.putData(f.withMode(mode).withMTime(System.currentTimeMillis()));
+                    remoteTx.putData(f.withMode(mode).withCurrentMTime());
                    return true;
                } else {
                    throw new IllegalArgumentException(uuid + " is not a file");
@@ -410,7 +411,7 @@ public class DhfsFileServiceImpl implements DhfsFileService {
            if (existingEnd < offset) {
                if (!pendingPrefix.isEmpty()) {
                    int diff = Math.toIntExact(offset - existingEnd);
-                    pendingPrefix = pendingPrefix.concat(ByteString.copyFrom(new byte[diff]));
+                    pendingPrefix = pendingPrefix.concat(UnsafeByteOperations.unsafeWrap(ByteBuffer.allocateDirect(diff)));
                } else {
                    fillZeros(existingEnd, offset, newChunks);
                    start = offset;
@@ -452,7 +453,7 @@ public class DhfsFileServiceImpl implements DhfsFileService {
                jMapHelper.put(file, JMapLongKey.of(e.getKey()), e.getValue());
            }

-            remoteTx.putData(file);
+            remoteTx.putData(file.withCurrentMTime());

            return (long) data.size();
        });
@@ -543,7 +544,7 @@ public class DhfsFileServiceImpl implements DhfsFileService {
                jMapHelper.put(file, JMapLongKey.of(e.getKey()), e.getValue());
            }

-            remoteTx.putData(file);
+            remoteTx.putData(file.withCurrentMTime());
            return true;
        });
    }
@@ -572,7 +573,7 @@ public class DhfsFileServiceImpl implements DhfsFileService {
                }

                if (!zeroCache.containsKey(end - cur))
-                    zeroCache.put(end - cur, createChunk(UnsafeByteOperations.unsafeWrap(new byte[Math.toIntExact(end - cur)])));
+                    zeroCache.put(end - cur, createChunk(UnsafeByteOperations.unsafeWrap(ByteBuffer.allocateDirect(Math.toIntExact(end - cur)))));

                ChunkData newChunkData = zeroCache.get(end - cur);
                newChunks.put(start, newChunkData.key());
--- a/dhfs-parent/dhfs-fs/src/test/java/com/usatiuk/dhfs/files/DhfsFileServiceSimpleTestImpl.java
+++ b/dhfs-parent/dhfs-fs/src/test/java/com/usatiuk/dhfs/files/DhfsFileServiceSimpleTestImpl.java
@@ -111,6 +111,7 @@ public abstract class DhfsFileServiceSimpleTestImpl {

        var uuid = ret.get();

+        var curMtime = fileService.getattr(uuid).get().mtime();
        fileService.write(uuid, 0, new byte[]{0, 1, 2, 3, 4, 5, 6, 7, 8, 9});
        Assertions.assertArrayEquals(new byte[]{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}, fileService.read(uuid, 0, 10).get().toByteArray());
        Assertions.assertArrayEquals(new byte[]{2, 3, 4, 5, 6, 7, 8, 9}, fileService.read(uuid, 2, 8).get().toByteArray());
@@ -123,6 +124,9 @@ public abstract class DhfsFileServiceSimpleTestImpl {
        fileService.write(uuid, 3, new byte[]{17, 18});
        Assertions.assertArrayEquals(new byte[]{0, 1, 2, 17, 18, 11, 15, 16, 8, 9, 13, 14}, fileService.read(uuid, 0, 12).get().toByteArray());

+        var newMtime = fileService.getattr(uuid).get().mtime();
+        Assertions.assertTrue(newMtime > curMtime);
+        
        fileService.unlink("/writeTest");
        Assertions.assertFalse(fileService.open("/writeTest").isPresent());
    }
--- a/dhfs-parent/dhfs-fs/src/test/resources/application.properties
+++ b/dhfs-parent/dhfs-fs/src/test/resources/application.properties
@@ -5,7 +5,6 @@ dhfs.objects.ref_verification=true
 dhfs.objects.deletion.delay=0
 quarkus.log.category."com.usatiuk.dhfs".level=TRACE
 quarkus.log.category."com.usatiuk.dhfs".min-level=TRACE
-quarkus.class-loading.parent-first-artifacts=com.usatiuk.dhfs:supportlib
 quarkus.http.test-port=0
 quarkus.http.test-ssl-port=0
 dhfs.local-discovery=false
--- a/dhfs-parent/dhfs-fuse/pom.xml
+++ b/dhfs-parent/dhfs-fuse/pom.xml
@@ -73,24 +73,9 @@
            <scope>test</scope>
        </dependency>
        <dependency>
-            <groupId>com.github.SerCeMan</groupId>
+            <groupId>com.github.serceman</groupId>
            <artifactId>jnr-fuse</artifactId>
-            <version>44ed40f8ce</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-ffi</artifactId>
-            <version>2.2.16</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-posix</artifactId>
-            <version>3.1.19</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-constants</artifactId>
-            <version>0.10.4</version>
+            <version>0.5.8</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
@@ -127,11 +112,6 @@
            <artifactId>kleppmanntree</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
-        <dependency>
-            <groupId>com.usatiuk.dhfs</groupId>
-            <artifactId>supportlib</artifactId>
-            <version>1.0-SNAPSHOT</version>
-        </dependency>
        <dependency>
            <groupId>com.usatiuk.dhfs</groupId>
            <artifactId>objects</artifactId>
--- a/dhfs-parent/dhfs-fuse/src/main/java/com/usatiuk/dhfs/fuse/DhfsFuse.java
+++ b/dhfs-parent/dhfs-fuse/src/main/java/com/usatiuk/dhfs/fuse/DhfsFuse.java
@@ -5,7 +5,6 @@ import com.sun.security.auth.module.UnixSystem;
 import com.usatiuk.dhfs.files.service.DhfsFileService;
 import com.usatiuk.dhfs.files.service.DirectoryNotEmptyException;
 import com.usatiuk.dhfs.files.service.GetattrRes;
-import com.usatiuk.dhfs.supportlib.UninitializedByteBuffer;
 import com.usatiuk.kleppmanntree.AlreadyExistsException;
 import com.usatiuk.objects.JObjectKey;
 import io.grpc.Status;
@@ -28,6 +27,7 @@ import ru.serce.jnrfuse.struct.FuseFileInfo;
 import ru.serce.jnrfuse.struct.Statvfs;
 import ru.serce.jnrfuse.struct.Timespec;

+import java.nio.ByteBuffer;
 import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Optional;
@@ -237,7 +237,7 @@ public class DhfsFuse extends FuseStubFS {
        if (offset < 0) return -ErrorCodes.EINVAL();
        try {
            var fileKey = getFromHandle(fi.fh.get());
-            var buffer = UninitializedByteBuffer.allocateUninitialized((int) size);
+            var buffer = ByteBuffer.allocateDirect((int) size);

            if (buffer.isDirect()) {
                jnrPtrByteOutputAccessors.getUnsafe().copyMemory(
--- a/dhfs-parent/dhfs-fuse/src/test/resources/application.properties
+++ b/dhfs-parent/dhfs-fuse/src/test/resources/application.properties
@@ -5,7 +5,6 @@ dhfs.objects.ref_verification=true
 dhfs.objects.deletion.delay=0
 quarkus.log.category."com.usatiuk.dhfs".level=TRACE
 quarkus.log.category."com.usatiuk.dhfs".min-level=TRACE
-quarkus.class-loading.parent-first-artifacts=com.usatiuk.dhfs:supportlib
 quarkus.http.test-port=0
 quarkus.http.test-ssl-port=0
 dhfs.local-discovery=false
--- a/dhfs-parent/objects/pom.xml
+++ b/dhfs-parent/objects/pom.xml
@@ -18,6 +18,11 @@
    </properties>

    <dependencies>
+        <dependency>
+            <groupId>net.jqwik</groupId>
+            <artifactId>jqwik</artifactId>
+            <scope>test</scope>
+        </dependency>
        <dependency>
            <groupId>io.quarkus</groupId>
            <artifactId>quarkus-junit5</artifactId>
@@ -54,11 +59,6 @@
            <artifactId>utils</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
-        <dependency>
-            <groupId>com.usatiuk.dhfs</groupId>
-            <artifactId>supportlib</artifactId>
-            <version>1.0-SNAPSHOT</version>
-        </dependency>
        <dependency>
            <groupId>io.quarkus</groupId>
            <artifactId>quarkus-junit5-mockito</artifactId>
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JDataVersionedWrapper.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JDataVersionedWrapper.java
@@ -1,6 +1,13 @@
 package com.usatiuk.objects;

-public interface JDataVersionedWrapper {
+import com.usatiuk.objects.iterators.Data;
+
+public sealed interface JDataVersionedWrapper extends Data<JDataVersionedWrapper> permits JDataVersionedWrapperLazy, JDataVersionedWrapperImpl {
+    @Override
+    default JDataVersionedWrapper value() {
+        return this;
+    }
+
    JData data();

    long version();
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JDataVersionedWrapperLazy.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JDataVersionedWrapperLazy.java
@@ -2,11 +2,11 @@ package com.usatiuk.objects;

 import java.util.function.Supplier;

-public class JDataVersionedWrapperLazy implements JDataVersionedWrapper {
+public final class JDataVersionedWrapperLazy implements JDataVersionedWrapper {
+    private JData _data;
    private final long _version;
    private final int _estimatedSize;
    private Supplier<JData> _producer;
-    private JData _data;

    public JDataVersionedWrapperLazy(long version, int estimatedSize, Supplier<JData> producer) {
        _version = version;
@@ -14,6 +14,18 @@ public class JDataVersionedWrapperLazy implements JDataVersionedWrapper {
        _producer = producer;
    }

+    public void setCacheCallback(Runnable cacheCallback) {
+        if (_data != null) {
+            throw new IllegalStateException("Cache callback can be set only before data is loaded");
+        }
+        var oldProducer = _producer;
+        _producer = () -> {
+            var ret = oldProducer.get();
+            cacheCallback.run();
+            return ret;
+        };
+    }
+
    public JData data() {
        if (_data != null)
            return _data;
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JDataVersionedWrapperSerializer.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JDataVersionedWrapperSerializer.java
@@ -2,12 +2,12 @@ package com.usatiuk.objects;


 import com.google.protobuf.ByteString;
-import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.inject.Inject;
+import jakarta.inject.Singleton;

 import java.nio.ByteBuffer;

-@ApplicationScoped
+@Singleton
 public class JDataVersionedWrapperSerializer implements ObjectSerializer<JDataVersionedWrapper> {
    @Inject
    ObjectSerializer<JData> dataSerializer;
@@ -24,6 +24,8 @@ public class JDataVersionedWrapperSerializer implements ObjectSerializer<JDataVe
    public JDataVersionedWrapper deserialize(ByteString data) {
        var version = data.substring(0, Long.BYTES).asReadOnlyByteBuffer().getLong();
        var rawData = data.substring(Long.BYTES);
-        return new JDataVersionedWrapperLazy(version, rawData.size(), () -> dataSerializer.deserialize(rawData));
+        return new JDataVersionedWrapperLazy(version, rawData.size(),
+                () -> dataSerializer.deserialize(rawData)
+        );
    }
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKey.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKey.java
@@ -26,11 +26,13 @@ public sealed interface JObjectKey extends Serializable, Comparable<JObjectKey>
    }

    static JObjectKey fromBytes(byte[] bytes) {
-        return new JObjectKeyImpl(new String(bytes, StandardCharsets.UTF_8));
+        return new JObjectKeyImpl(new String(bytes, StandardCharsets.ISO_8859_1));
    }

    static JObjectKey fromByteBuffer(ByteBuffer buff) {
-        return new JObjectKeyImpl(StandardCharsets.UTF_8.decode(buff).toString());
+        byte[] bytes = new byte[buff.remaining()];
+        buff.get(bytes);
+        return new JObjectKeyImpl(bytes);
    }

    @Override
@@ -39,8 +41,6 @@ public sealed interface JObjectKey extends Serializable, Comparable<JObjectKey>
    @Override
    String toString();

-    byte[] bytes();
-
    ByteBuffer toByteBuffer();

    String value();
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKeyImpl.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKeyImpl.java
@@ -1,11 +1,24 @@
 package com.usatiuk.objects;

-import com.usatiuk.dhfs.supportlib.UninitializedByteBuffer;
-
+import java.io.Serial;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
+import java.util.Objects;
+
+public final class JObjectKeyImpl implements JObjectKey {
+    @Serial
+    private static final long serialVersionUID = 0L;
+    private final String value;
+    private transient ByteBuffer _bb = null;
+
+    public JObjectKeyImpl(String value) {
+        this.value = value;
+    }
+
+    public JObjectKeyImpl(byte[] bytes) {
+        this.value = new String(bytes, StandardCharsets.ISO_8859_1);
+    }

-public record JObjectKeyImpl(String value) implements JObjectKey {
    @Override
    public int compareTo(JObjectKey o) {
        switch (o) {
@@ -27,17 +40,36 @@ public record JObjectKeyImpl(String value) implements JObjectKey {
    }

    @Override
-    public byte[] bytes() {
-        return value.getBytes(StandardCharsets.UTF_8);
+    public ByteBuffer toByteBuffer() {
+        if (_bb != null) return _bb;
+
+        synchronized (this) {
+            if (_bb != null) return _bb;
+            var bytes = value.getBytes(StandardCharsets.ISO_8859_1);
+            var directBb = ByteBuffer.allocateDirect(bytes.length);
+            directBb.put(bytes);
+            directBb.flip();
+            _bb = directBb;
+            return directBb;
+        }
    }

    @Override
-    public ByteBuffer toByteBuffer() {
-        var heapBb = StandardCharsets.UTF_8.encode(value);
-        if (heapBb.isDirect()) return heapBb;
-        var directBb = UninitializedByteBuffer.allocateUninitialized(heapBb.remaining());
-        directBb.put(heapBb);
-        directBb.flip();
-        return directBb;
+    public String value() {
+        return value;
    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == this) return true;
+        if (obj == null || obj.getClass() != this.getClass()) return false;
+        var that = (JObjectKeyImpl) obj;
+        return Objects.equals(this.value, that.value);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(value);
+    }
+
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKeyMax.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKeyMax.java
@@ -18,11 +18,6 @@ public record JObjectKeyMax() implements JObjectKey {
        }
    }

-    @Override
-    public byte[] bytes() {
-        throw new UnsupportedOperationException();
-    }
-
    @Override
    public ByteBuffer toByteBuffer() {
        throw new UnsupportedOperationException();
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKeyMin.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKeyMin.java
@@ -18,11 +18,6 @@ public record JObjectKeyMin() implements JObjectKey {
        }
    }

-    @Override
-    public byte[] bytes() {
-        throw new UnsupportedOperationException();
-    }
-
    @Override
    public ByteBuffer toByteBuffer() {
        throw new UnsupportedOperationException();
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/Data.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/Data.java
@@ -2,9 +2,6 @@ package com.usatiuk.objects.iterators;

 import java.util.Optional;

-public record Data<V>(V value) implements MaybeTombstone<V> {
-    @Override
-    public Optional<V> opt() {
-        return Optional.of(value);
-    }
+public interface Data<V> extends MaybeTombstone<V> {
+    V value();
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/DataWrapper.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/DataWrapper.java
@@ -0,0 +1,6 @@
+package com.usatiuk.objects.iterators;
+
+import java.util.Optional;
+
+public record DataWrapper<V>(V value) implements Data<V> {
+}
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/MaybeTombstone.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/MaybeTombstone.java
@@ -3,5 +3,4 @@ package com.usatiuk.objects.iterators;
 import java.util.Optional;

 public interface MaybeTombstone<T> {
-    Optional<T> opt();
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/MergingKvIterator.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/MergingKvIterator.java
@@ -1,25 +1,37 @@
 package com.usatiuk.objects.iterators;

 import io.quarkus.logging.Log;
+import org.apache.commons.lang3.mutable.MutableObject;
 import org.apache.commons.lang3.tuple.Pair;

-import java.util.*;
-import java.util.stream.IntStream;
+import java.util.List;
+import java.util.NavigableMap;
+import java.util.NoSuchElementException;
+import java.util.TreeMap;

 public class MergingKvIterator<K extends Comparable<K>, V> extends ReversibleKvIterator<K, V> {
-    private final NavigableMap<K, CloseableKvIterator<K, V>> _sortedIterators = new TreeMap<>();
+    private record IteratorEntry<K extends Comparable<K>, V>(int priority, CloseableKvIterator<K, V> iterator) {
+        public IteratorEntry<K, V> reversed() {
+            return new IteratorEntry<>(priority, iterator.reversed());
+        }
+    }
+
+    private final NavigableMap<K, IteratorEntry<K, V>> _sortedIterators = new TreeMap<>();
    private final String _name;
-    private final Map<CloseableKvIterator<K, V>, Integer> _iterators;
+    private final List<IteratorEntry<K, V>> _iterators;

    public MergingKvIterator(String name, IteratorStart startType, K startKey, List<IterProdFn<K, V>> iterators) {
        _goingForward = true;
        _name = name;

-        _iterators = Map.ofEntries(
-                IntStream.range(0, iterators.size())
-                        .mapToObj(i -> Pair.of(iterators.get(i).get(startType, startKey), i))
-                        .toArray(Pair[]::new)
-        );
+        // Why streams are so slow?
+        {
+            IteratorEntry<K, V>[] iteratorEntries = new IteratorEntry[iterators.size()];
+            for (int i = 0; i < iterators.size(); i++) {
+                iteratorEntries[i] = new IteratorEntry<>(i, iterators.get(i).get(startType, startKey));
+            }
+            _iterators = List.of(iteratorEntries);
+        }

        if (startType == IteratorStart.LT || startType == IteratorStart.LE) {
            // Starting at a greatest key less than/less or equal than:
@@ -30,7 +42,8 @@ public class MergingKvIterator<K extends Comparable<K>, V> extends ReversibleKvI
            K greatestLess = null;
            K smallestMore = null;

-            for (var it : _iterators.keySet()) {
+            for (var ite : _iterators) {
+                var it = ite.iterator();
                if (it.hasNext()) {
                    var peeked = it.peekNextKey();
                    if (startType == IteratorStart.LE ? peeked.compareTo(startKey) <= 0 : peeked.compareTo(startKey) < 0) {
@@ -55,14 +68,15 @@ public class MergingKvIterator<K extends Comparable<K>, V> extends ReversibleKvI
                // Empty iterators
            }

-            for (var iterator : _iterators.keySet()) {
+            for (var ite : _iterators) {
+                var iterator = ite.iterator();
                while (iterator.hasNext() && iterator.peekNextKey().compareTo(initialMaxValue) < 0) {
                    iterator.skip();
                }
            }
        }

-        for (CloseableKvIterator<K, V> iterator : _iterators.keySet()) {
+        for (IteratorEntry<K, V> iterator : _iterators) {
            advanceIterator(iterator);
        }

@@ -88,29 +102,39 @@ public class MergingKvIterator<K extends Comparable<K>, V> extends ReversibleKvI
        this(name, startType, startKey, List.of(iterators));
    }

-    private void advanceIterator(CloseableKvIterator<K, V> iterator) {
-        if (!iterator.hasNext()) {
-            return;
-        }
+    private void advanceIterator(IteratorEntry<K, V> iteratorEntry) {
+        while (iteratorEntry.iterator().hasNext()) {
+            K key = iteratorEntry.iterator().peekNextKey();
+            Log.tracev("{0} Advance peeked: {1}-{2}", _name, iteratorEntry, key);

-        K key = iterator.peekNextKey();
-        Log.tracev("{0} Advance peeked: {1}-{2}", _name, iterator, key);
-        if (!_sortedIterators.containsKey(key)) {
-            _sortedIterators.put(key, iterator);
-            return;
-        }
+            MutableObject<IteratorEntry<K, V>> mutableBoolean = new MutableObject<>(null);

-        // Expects that reversed iterator returns itself when reversed again
-        var oursPrio = _iterators.get(_goingForward ? iterator : iterator.reversed());
-        var them = _sortedIterators.get(key);
-        var theirsPrio = _iterators.get(_goingForward ? them : them.reversed());
-        if (oursPrio < theirsPrio) {
-            _sortedIterators.put(key, iterator);
-            advanceIterator(them);
-        } else {
-            Log.tracev("{0} Skipped: {1}", _name, iterator.peekNextKey());
-            iterator.skip();
-            advanceIterator(iterator);
+            var newVal = _sortedIterators.merge(key, iteratorEntry, (theirsEntry, oldValOurs) -> {
+                var oursPrio = oldValOurs.priority();
+                var theirsPrio = theirsEntry.priority();
+
+                if (oursPrio < theirsPrio) {
+                    mutableBoolean.setValue(theirsEntry);
+                    return oldValOurs;
+                    // advance them
+                    // return
+                } else {
+                    return theirsEntry;
+                    // skip, continue
+                }
+            });
+
+            if (newVal != iteratorEntry) {
+                Log.tracev("{0} Skipped: {1}", _name, iteratorEntry.iterator().peekNextKey());
+                iteratorEntry.iterator().skip();
+                continue;
+            }
+
+            if (mutableBoolean.getValue() != null) {
+                advanceIterator(mutableBoolean.getValue());
+                return;
+            }
+            return;
        }
    }

@@ -120,7 +144,7 @@ public class MergingKvIterator<K extends Comparable<K>, V> extends ReversibleKvI
        Log.tracev("{0} Reversing from {1}", _name, cur);
        _goingForward = !_goingForward;
        _sortedIterators.clear();
-        for (CloseableKvIterator<K, V> iterator : _iterators.keySet()) {
+        for (IteratorEntry<K, V> iterator : _iterators) {
            // _goingForward inverted already
            advanceIterator(!_goingForward ? iterator.reversed() : iterator);
        }
@@ -150,7 +174,7 @@ public class MergingKvIterator<K extends Comparable<K>, V> extends ReversibleKvI
        if (cur == null) {
            throw new NoSuchElementException();
        }
-        cur.getValue().skip();
+        cur.getValue().iterator().skip();
        advanceIterator(cur.getValue());
        Log.tracev("{0} Skip: {1}, next: {2}", _name, cur, _sortedIterators);
    }
@@ -166,7 +190,7 @@ public class MergingKvIterator<K extends Comparable<K>, V> extends ReversibleKvI
        if (cur == null) {
            throw new NoSuchElementException();
        }
-        var curVal = cur.getValue().next();
+        var curVal = cur.getValue().iterator().next();
        advanceIterator(cur.getValue());
 //        Log.tracev("{0} Read from {1}: {2}, next: {3}", _name, cur.getValue(), curVal, _sortedIterators.keySet());
        return curVal;
@@ -174,8 +198,8 @@ public class MergingKvIterator<K extends Comparable<K>, V> extends ReversibleKvI

    @Override
    public void close() {
-        for (CloseableKvIterator<K, V> iterator : _iterators.keySet()) {
-            iterator.close();
+        for (IteratorEntry<K, V> iterator : _iterators) {
+            iterator.iterator().close();
        }
    }

--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/NavigableMapKvIterator.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/NavigableMapKvIterator.java
@@ -9,22 +9,22 @@ public class NavigableMapKvIterator<K extends Comparable<K>, V> extends Reversib
    private Iterator<Map.Entry<K, V>> _iterator;
    private Map.Entry<K, V> _next;

-    public NavigableMapKvIterator(NavigableMap<K, V> map, IteratorStart start, K key) {
-        _map = map;
+    public NavigableMapKvIterator(NavigableMap<K, ? extends V> map, IteratorStart start, K key) {
+        _map = (NavigableMap<K, V>) map;
        SortedMap<K, V> _view;
        _goingForward = true;
        switch (start) {
-            case GE -> _view = map.tailMap(key, true);
-            case GT -> _view = map.tailMap(key, false);
+            case GE -> _view = _map.tailMap(key, true);
+            case GT -> _view = _map.tailMap(key, false);
            case LE -> {
-                var floorKey = map.floorKey(key);
+                var floorKey = _map.floorKey(key);
                if (floorKey == null) _view = _map;
-                else _view = map.tailMap(floorKey, true);
+                else _view = _map.tailMap(floorKey, true);
            }
            case LT -> {
                var lowerKey = map.lowerKey(key);
                if (lowerKey == null) _view = _map;
-                else _view = map.tailMap(lowerKey, true);
+                else _view = _map.tailMap(lowerKey, true);
            }
            default -> throw new IllegalArgumentException("Unknown start type");
        }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/Tombstone.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/Tombstone.java
@@ -2,9 +2,5 @@ package com.usatiuk.objects.iterators;

 import java.util.Optional;

-public record Tombstone<V>() implements MaybeTombstone<V> {
-    @Override
-    public Optional<V> opt() {
-        return Optional.empty();
-    }
+public interface Tombstone<V> extends MaybeTombstone<V> {
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/TombstoneImpl.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/TombstoneImpl.java
@@ -0,0 +1,4 @@
+package com.usatiuk.objects.iterators;
+
+public record TombstoneImpl<V>() implements Tombstone<V> {
+}
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/TombstoneMergingKvIterator.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/iterators/TombstoneMergingKvIterator.java
@@ -1,83 +1,24 @@
 package com.usatiuk.objects.iterators;

 import io.quarkus.logging.Log;
-import org.apache.commons.lang3.tuple.Pair;

 import java.util.List;

-public class TombstoneMergingKvIterator<K extends Comparable<K>, V> implements CloseableKvIterator<K, V> {
-    private final CloseableKvIterator<K, V> _backing;
-    private final String _name;
-
-    public TombstoneMergingKvIterator(String name, IteratorStart startType, K startKey, List<IterProdFn<K, MaybeTombstone<V>>> iterators) {
-        _name = name;
-        _backing = new PredicateKvIterator<>(
-                new MergingKvIterator<>(name + "-merging", startType, startKey, iterators),
+public abstract class TombstoneMergingKvIterator {
+    public static <K extends Comparable<K>, V> CloseableKvIterator<K, V> of(String name, IteratorStart startType, K startKey, List<IterProdFn<K, MaybeTombstone<V>>> iterators) {
+        return new PredicateKvIterator<K, MaybeTombstone<V>, V>(
+                new MergingKvIterator<K, MaybeTombstone<V>>(name + "-merging", startType, startKey, iterators),
                startType, startKey,
                pair -> {
-                    Log.tracev("{0} - Processing pair {1}", _name, pair);
-                    if (pair instanceof Tombstone) {
+                    Log.tracev("{0} - Processing pair {1}", name, pair);
+                    if (pair instanceof Tombstone<V>) {
                        return null;
                    }
                    return ((Data<V>) pair).value();
                });
    }

-    @SafeVarargs
-    public TombstoneMergingKvIterator(String name, IteratorStart startType, K startKey, IterProdFn<K, MaybeTombstone<V>>... iterators) {
-        this(name, startType, startKey, List.of(iterators));
-    }
-
-    @Override
-    public K peekNextKey() {
-        return _backing.peekNextKey();
-    }
-
-    @Override
-    public void skip() {
-        _backing.skip();
-    }
-
-    @Override
-    public K peekPrevKey() {
-        return _backing.peekPrevKey();
-    }
-
-    @Override
-    public Pair<K, V> prev() {
-        return _backing.prev();
-    }
-
-    @Override
-    public boolean hasPrev() {
-        return _backing.hasPrev();
-    }
-
-    @Override
-    public void skipPrev() {
-        _backing.skipPrev();
-    }
-
-    @Override
-    public void close() {
-        _backing.close();
-    }
-
-    @Override
-    public boolean hasNext() {
-        return _backing.hasNext();
-    }
-
-    @Override
-    public Pair<K, V> next() {
-        return _backing.next();
-    }
-
-    @Override
-    public String toString() {
-        return "TombstoneMergingKvIterator{" +
-                "_backing=" + _backing +
-                ", _name='" + _name + '\'' +
-                '}';
+    public static <K extends Comparable<K>, V> CloseableKvIterator<K, V> of(String name, IteratorStart startType, K startKey, IterProdFn<K, MaybeTombstone<V>>... iterators) {
+        return of(name, startType, startKey, List.of(iterators));
    }
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/snapshot/SnapshotManager.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/snapshot/SnapshotManager.java
@@ -6,13 +6,14 @@ import com.usatiuk.objects.stores.WritebackObjectPersistentStore;
 import com.usatiuk.objects.transaction.TxRecord;
 import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.inject.Inject;
+import jakarta.inject.Singleton;

 import javax.annotation.Nonnull;
 import java.util.Collection;
 import java.util.Optional;
 import java.util.function.Consumer;

-@ApplicationScoped
+@Singleton
 public class SnapshotManager {
    @Inject
    WritebackObjectPersistentStore writebackStore;
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/CachingObjectPersistentStore.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/CachingObjectPersistentStore.java
@@ -1,6 +1,7 @@
 package com.usatiuk.objects.stores;

 import com.usatiuk.objects.JDataVersionedWrapper;
+import com.usatiuk.objects.JDataVersionedWrapperLazy;
 import com.usatiuk.objects.JObjectKey;
 import com.usatiuk.objects.iterators.*;
 import com.usatiuk.objects.snapshot.Snapshot;
@@ -33,10 +34,9 @@ public class CachingObjectPersistentStore {
                         long version,
                         int sizeLimit) {
        public Cache withPut(JObjectKey key, Optional<JDataVersionedWrapper> obj) {
-            int objSize = obj.map(JDataVersionedWrapper::estimateSize).orElse(16);
+            var entry = obj.<CacheEntry>map(o -> new CacheEntryPresent(o, o.estimateSize())).orElse(new CacheEntryMiss());

-            int newSize = size() + objSize;
-            var entry = new CacheEntry(obj.<MaybeTombstone<JDataVersionedWrapper>>map(Data::new).orElse(new Tombstone<>()), objSize);
+            int newSize = size() + entry.size();

            var old = map.get(key);
            if (old != null)
@@ -141,10 +141,11 @@ public class CachingObjectPersistentStore {
                Cache finalCurCache = curCache;
                return new Snapshot<JObjectKey, JDataVersionedWrapper>() {
                    private boolean _invalid = false;
+                    private boolean _closed = false;
                    private final Cache _curCache = finalCurCache;
                    private final Snapshot<JObjectKey, JDataVersionedWrapper> _backing = finalBacking;

-                    private void maybeCache(JObjectKey key, Optional<JDataVersionedWrapper> obj) {
+                    private void doCache(JObjectKey key, Optional<JDataVersionedWrapper> obj) {
                        _cacheTries.incrementAndGet();
                        if (_invalid)
                            return;
@@ -160,18 +161,34 @@ public class CachingObjectPersistentStore {
                            _cached.incrementAndGet();
                    }

+                    private void maybeCache(JObjectKey key, Optional<JDataVersionedWrapper> obj) {
+                        if (obj.isEmpty()) {
+                            doCache(key, obj);
+                            return;
+                        }
+
+                        var wrapper = obj.get();
+
+                        if (!(wrapper instanceof JDataVersionedWrapperLazy lazy)) {
+                            doCache(key, obj);
+                            return;
+                        }
+
+                        lazy.setCacheCallback(() -> {
+                            if (_closed) {
+                                Log.error("Cache callback called after close");
+                                System.exit(-1);
+                            }
+                            doCache(key, obj);
+                        });
+                        return;
+                    }
+
                    @Override
                    public CloseableKvIterator<JObjectKey, JDataVersionedWrapper> getIterator(IteratorStart start, JObjectKey key) {
-                        return new TombstoneMergingKvIterator<>("cache", start, key,
-                                (mS, mK)
-                                        -> new MappingKvIterator<>(
-                                        new NavigableMapKvIterator<>(_curCache.map(), mS, mK),
-                                        e -> {
-//                                        Log.tracev("Taken from cache: {0}", e);
-                                            return e.object();
-                                        }
-                                ),
-                                (mS, mK) -> new MappingKvIterator<>(new CachingKvIterator(_backing.getIterator(start, key)), Data::new));
+                        return TombstoneMergingKvIterator.<JObjectKey, JDataVersionedWrapper>of("cache", start, key,
+                                (mS, mK) -> new NavigableMapKvIterator<JObjectKey, MaybeTombstone<JDataVersionedWrapper>>(_curCache.map(), mS, mK),
+                                (mS, mK) -> new CachingKvIterator(_backing.getIterator(start, key)));
                    }

                    @Nonnull
@@ -179,12 +196,12 @@ public class CachingObjectPersistentStore {
                    public Optional<JDataVersionedWrapper> readObject(JObjectKey name) {
                        var cached = _curCache.map().get(name);
                        if (cached != null) {
-                            return switch (cached.object()) {
-                                case Data<JDataVersionedWrapper> data -> Optional.of(data.value());
-                                case Tombstone<JDataVersionedWrapper> tombstone -> {
+                            return switch (cached) {
+                                case CacheEntryPresent data -> Optional.of(data.value());
+                                case CacheEntryMiss tombstone -> {
                                    yield Optional.empty();
                                }
-                                default -> throw new IllegalStateException("Unexpected value: " + cached.object());
+                                default -> throw new IllegalStateException("Unexpected value: " + cached);
                            };
                        }
                        var read = _backing.readObject(name);
@@ -199,10 +216,11 @@ public class CachingObjectPersistentStore {

                    @Override
                    public void close() {
+                        _closed = true;
                        _backing.close();
                    }

-                    private class CachingKvIterator implements CloseableKvIterator<JObjectKey, JDataVersionedWrapper> {
+                    private class CachingKvIterator implements CloseableKvIterator<JObjectKey, MaybeTombstone<JDataVersionedWrapper>> {
                        private final CloseableKvIterator<JObjectKey, JDataVersionedWrapper> _delegate;

                        private CachingKvIterator(CloseableKvIterator<JObjectKey, JDataVersionedWrapper> delegate) {
@@ -235,10 +253,10 @@ public class CachingObjectPersistentStore {
                        }

                        @Override
-                        public Pair<JObjectKey, JDataVersionedWrapper> prev() {
+                        public Pair<JObjectKey, MaybeTombstone<JDataVersionedWrapper>> prev() {
                            var prev = _delegate.prev();
                            maybeCache(prev.getKey(), Optional.of(prev.getValue()));
-                            return prev;
+                            return (Pair<JObjectKey, MaybeTombstone<JDataVersionedWrapper>>) (Pair<JObjectKey, ?>) prev;
                        }

                        @Override
@@ -252,10 +270,10 @@ public class CachingObjectPersistentStore {
                        }

                        @Override
-                        public Pair<JObjectKey, JDataVersionedWrapper> next() {
+                        public Pair<JObjectKey, MaybeTombstone<JDataVersionedWrapper>> next() {
                            var next = _delegate.next();
                            maybeCache(next.getKey(), Optional.of(next.getValue()));
-                            return next;
+                            return (Pair<JObjectKey, MaybeTombstone<JDataVersionedWrapper>>) (Pair<JObjectKey, ?>) next;
                        }
                    }
                };
@@ -268,6 +286,18 @@ public class CachingObjectPersistentStore {
        }
    }

-    private record CacheEntry(MaybeTombstone<JDataVersionedWrapper> object, int size) {
+    private interface CacheEntry extends MaybeTombstone<JDataVersionedWrapper> {
+        int size();
+    }
+
+    private record CacheEntryPresent(JDataVersionedWrapper value,
+                                     int size) implements CacheEntry, Data<JDataVersionedWrapper> {
+    }
+
+    private record CacheEntryMiss() implements CacheEntry, Tombstone<JDataVersionedWrapper> {
+        @Override
+        public int size() {
+            return 64;
+        }
    }
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/LmdbObjectPersistentStore.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/LmdbObjectPersistentStore.java
@@ -2,6 +2,7 @@ package com.usatiuk.objects.stores;

 import com.google.protobuf.ByteString;
 import com.google.protobuf.UnsafeByteOperations;
+import com.usatiuk.dhfs.utils.RefcountedCloseable;
 import com.usatiuk.objects.JObjectKey;
 import com.usatiuk.objects.JObjectKeyMax;
 import com.usatiuk.objects.JObjectKeyMin;
@@ -10,8 +11,6 @@ import com.usatiuk.objects.iterators.IteratorStart;
 import com.usatiuk.objects.iterators.KeyPredicateKvIterator;
 import com.usatiuk.objects.iterators.ReversibleKvIterator;
 import com.usatiuk.objects.snapshot.Snapshot;
-import com.usatiuk.dhfs.supportlib.UninitializedByteBuffer;
-import com.usatiuk.dhfs.utils.RefcountedCloseable;
 import io.quarkus.arc.properties.IfBuildProperty;
 import io.quarkus.logging.Log;
 import io.quarkus.runtime.ShutdownEvent;
@@ -30,7 +29,6 @@ import java.lang.ref.Cleaner;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
-import java.util.Arrays;
 import java.util.NoSuchElementException;
 import java.util.Optional;

@@ -41,7 +39,17 @@ import static org.lmdbjava.Env.create;
@IfBuildProperty(name = "dhfs.objects.persistence", stringValue = "lmdb")
 public class LmdbObjectPersistentStore implements ObjectPersistentStore {
    private static final String DB_NAME = "objects";
-    private static final byte[] DB_VER_OBJ_NAME = "__DB_VER_OBJ".getBytes(StandardCharsets.UTF_8);
+    private static final String DB_VER_OBJ_NAME_STR = "__DB_VER_OBJ";
+    private static final ByteBuffer DB_VER_OBJ_NAME;
+
+    static {
+        byte[] tmp = DB_VER_OBJ_NAME_STR.getBytes(StandardCharsets.ISO_8859_1);
+        var bb = ByteBuffer.allocateDirect(tmp.length);
+        bb.put(tmp);
+        bb.flip();
+        DB_VER_OBJ_NAME = bb.asReadOnlyBuffer();
+    }
+
    private final Path _root;
    private Env<ByteBuffer> _env;
    private Dbi<ByteBuffer> _db;
@@ -67,13 +75,10 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
            if (read.isPresent()) {
                Log.infov("Read tx id {0}", read.get());
            } else {
-                var bb = ByteBuffer.allocateDirect(DB_VER_OBJ_NAME.length);
-                bb.put(DB_VER_OBJ_NAME);
-                bb.flip();
                var bbData = ByteBuffer.allocateDirect(8);
                bbData.putLong(0);
                bbData.flip();
-                _db.put(txn, bb, bbData);
+                _db.put(txn, DB_VER_OBJ_NAME.asReadOnlyBuffer(), bbData);
                txn.commit();
            }
        }
@@ -82,10 +87,7 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
    }

    private Optional<Long> readTxId(Txn<ByteBuffer> txn) {
-        var bb = ByteBuffer.allocateDirect(DB_VER_OBJ_NAME.length);
-        bb.put(DB_VER_OBJ_NAME);
-        bb.flip();
-        var value = _db.get(txn, bb);
+        var value = _db.get(txn, DB_VER_OBJ_NAME.asReadOnlyBuffer());
        return Optional.ofNullable(value).map(ByteBuffer::getLong);
    }

@@ -121,7 +123,7 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
            @Override
            public CloseableKvIterator<JObjectKey, ByteString> getIterator(IteratorStart start, JObjectKey key) {
                assert !_closed;
-                return new KeyPredicateKvIterator<>(new LmdbKvIterator(_txn.ref(), start, key), start, key, (k) -> !Arrays.equals(k.value().getBytes(StandardCharsets.UTF_8), DB_VER_OBJ_NAME));
+                return new KeyPredicateKvIterator<>(new LmdbKvIterator(_txn.ref(), start, key), start, key, (k) -> !k.value().equals(DB_VER_OBJ_NAME_STR));
            }

            @Nonnull
@@ -129,12 +131,7 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
            public Optional<ByteString> readObject(JObjectKey name) {
                assert !_closed;
                var got = _db.get(_txn.get(), name.toByteBuffer());
-                var ret = Optional.ofNullable(got).map(read -> {
-                    var uninitBb = UninitializedByteBuffer.allocateUninitialized(got.remaining());
-                    uninitBb.put(got);
-                    uninitBb.flip();
-                    return UnsafeByteOperations.unsafeWrap(uninitBb);
-                });
+                var ret = Optional.ofNullable(got).map(UnsafeByteOperations::unsafeWrap);
                return ret;
            }

@@ -168,13 +165,10 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {

            assert txId > readTxId(txn).orElseThrow();

-            var bb = ByteBuffer.allocateDirect(DB_VER_OBJ_NAME.length);
-            bb.put(DB_VER_OBJ_NAME);
-            bb.flip();
            var bbData = ByteBuffer.allocateDirect(8);
            bbData.putLong(txId);
            bbData.flip();
-            _db.put(txn, bb, bbData);
+            _db.put(txn, DB_VER_OBJ_NAME.asReadOnlyBuffer(), bbData);
        } catch (Throwable t) {
            txn.close();
            throw t;
@@ -214,6 +208,7 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
        //        private final Exception _allocationStacktrace = new Exception();
        private final Exception _allocationStacktrace = null;
        private boolean _hasNext = false;
+        private JObjectKey _peekedNextKey = null;

        LmdbKvIterator(RefcountedCloseable<Txn<ByteBuffer>> txn, IteratorStart start, JObjectKey key) {
            _txn = txn;
@@ -283,24 +278,24 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
                }
            }

-            var realGot = JObjectKey.fromByteBuffer(_cursor.key());
-            _cursor.key().flip();
-
-            switch (start) {
-                case LT -> {
-//                    assert !_hasNext || realGot.compareTo(key) < 0;
-                }
-                case LE -> {
-//                    assert !_hasNext || realGot.compareTo(key) <= 0;
-                }
-                case GT -> {
-                    assert !_hasNext || realGot.compareTo(key) > 0;
-                }
-                case GE -> {
-                    assert !_hasNext || realGot.compareTo(key) >= 0;
-                }
-            }
-            Log.tracev("got: {0}, hasNext: {1}", realGot, _hasNext);
+//            var realGot = JObjectKey.fromByteBuffer(_cursor.key());
+//            _cursor.key().flip();
+//
+//            switch (start) {
+//                case LT -> {
+////                    assert !_hasNext || realGot.compareTo(key) < 0;
+//                }
+//                case LE -> {
+////                    assert !_hasNext || realGot.compareTo(key) <= 0;
+//                }
+//                case GT -> {
+//                    assert !_hasNext || realGot.compareTo(key) > 0;
+//                }
+//                case GE -> {
+//                    assert !_hasNext || realGot.compareTo(key) >= 0;
+//                }
+//            }
+//            Log.tracev("got: {0}, hasNext: {1}", realGot, _hasNext);
        }

        @Override
@@ -329,6 +324,7 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
                }
            }
            _goingForward = !_goingForward;
+            _peekedNextKey = null;
        }

        @Override
@@ -336,8 +332,12 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
            if (!_hasNext) {
                throw new NoSuchElementException("No more elements");
            }
+            if (_peekedNextKey != null) {
+                return _peekedNextKey;
+            }
            var ret = JObjectKey.fromByteBuffer(_cursor.key());
            _cursor.key().flip();
+            _peekedNextKey = ret;
            return ret;
        }

@@ -347,6 +347,7 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
                _hasNext = _cursor.next();
            else
                _hasNext = _cursor.prev();
+            _peekedNextKey = null;
        }

        @Override
@@ -360,18 +361,15 @@ public class LmdbObjectPersistentStore implements ObjectPersistentStore {
                throw new NoSuchElementException("No more elements");
            }
            // TODO: Right now with java serialization it doesn't matter, it's all copied to arrays anyway
-//            var val = _cursor.val();
-//            var bbDirect = UninitializedByteBuffer.allocateUninitialized(val.remaining());
-//            bbDirect.put(val);
-//            bbDirect.flip();
-//            var bs = UnsafeByteOperations.unsafeWrap(bbDirect);
-//            var ret = Pair.of(JObjectKey.fromByteBuffer(_cursor.key()), bs);
-            var ret = Pair.of(JObjectKey.fromByteBuffer(_cursor.key()), ByteString.copyFrom(_cursor.val()));
+            var val = _cursor.val();
+            var bs = UnsafeByteOperations.unsafeWrap(val);
+            var ret = Pair.of(JObjectKey.fromByteBuffer(_cursor.key()), bs);
            if (_goingForward)
                _hasNext = _cursor.next();
            else
                _hasNext = _cursor.prev();
            Log.tracev("Read: {0}, hasNext: {1}", ret, _hasNext);
+            _peekedNextKey = null;
            return ret;
        }
    }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/PendingDelete.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/PendingDelete.java
@@ -1,6 +1,9 @@
 package com.usatiuk.objects.stores;

+import com.usatiuk.objects.JDataVersionedWrapper;
 import com.usatiuk.objects.JObjectKey;
+import com.usatiuk.objects.iterators.Tombstone;

-public record PendingDelete(JObjectKey key, long bundleId) implements PendingWriteEntry {
+public record PendingDelete(JObjectKey key,
+                            long bundleId) implements PendingWriteEntry, Tombstone<JDataVersionedWrapper> {
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/PendingWrite.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/PendingWrite.java
@@ -1,6 +1,7 @@
 package com.usatiuk.objects.stores;

 import com.usatiuk.objects.JDataVersionedWrapper;
+import com.usatiuk.objects.iterators.Data;

-public record PendingWrite(JDataVersionedWrapper data, long bundleId) implements PendingWriteEntry {
+public record PendingWrite(JDataVersionedWrapper value, long bundleId) implements PendingWriteEntry, Data<JDataVersionedWrapper> {
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/PendingWriteEntry.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/PendingWriteEntry.java
@@ -1,5 +1,8 @@
 package com.usatiuk.objects.stores;

-public interface PendingWriteEntry {
+import com.usatiuk.objects.JDataVersionedWrapper;
+import com.usatiuk.objects.iterators.MaybeTombstone;
+
+public interface PendingWriteEntry extends MaybeTombstone<JDataVersionedWrapper> {
    long bundleId();
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/SerializingObjectPersistentStore.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/SerializingObjectPersistentStore.java
@@ -3,7 +3,6 @@ package com.usatiuk.objects.stores;
 import com.google.protobuf.ByteString;
 import com.usatiuk.objects.JDataVersionedWrapper;
 import com.usatiuk.objects.JObjectKey;
-import com.usatiuk.objects.JObjectKeyImpl;
 import com.usatiuk.objects.ObjectSerializer;
 import com.usatiuk.objects.iterators.CloseableKvIterator;
 import com.usatiuk.objects.iterators.IteratorStart;
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/WritebackObjectPersistentStore.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/WritebackObjectPersistentStore.java
@@ -350,15 +350,9 @@ public class WritebackObjectPersistentStore {

                @Override
                public CloseableKvIterator<JObjectKey, JDataVersionedWrapper> getIterator(IteratorStart start, JObjectKey key) {
-                    return new TombstoneMergingKvIterator<>("writeback-ps", start, key,
-                            (tS, tK) -> new MappingKvIterator<>(
-                                    new NavigableMapKvIterator<>(_pendingWrites, tS, tK),
-                                    e -> switch (e) {
-                                        case PendingWrite pw -> new Data<>(pw.data());
-                                        case PendingDelete d -> new Tombstone<>();
-                                        default -> throw new IllegalStateException("Unexpected value: " + e);
-                                    }),
-                            (tS, tK) -> new MappingKvIterator<>(_cache.getIterator(tS, tK), Data::new));
+                    return  TombstoneMergingKvIterator.<JObjectKey, JDataVersionedWrapper>of("writeback-ps", start, key,
+                            (tS, tK) -> new NavigableMapKvIterator<>(_pendingWrites, tS, tK),
+                            (tS, tK) -> (CloseableKvIterator<JObjectKey, MaybeTombstone<JDataVersionedWrapper>>) (CloseableKvIterator<JObjectKey, ?>) _cache.getIterator(tS, tK));
                }

                @Nonnull
@@ -367,7 +361,7 @@ public class WritebackObjectPersistentStore {
                    var cached = _pendingWrites.get(name);
                    if (cached != null) {
                        return switch (cached) {
-                            case PendingWrite c -> Optional.of(c.data());
+                            case PendingWrite c -> Optional.of(c.value());
                            case PendingDelete d -> {
                                yield Optional.empty();
                            }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/JObjectManager.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/JObjectManager.java
@@ -1,11 +1,12 @@
 package com.usatiuk.objects.transaction;

+import com.google.common.collect.Streams;
+import com.usatiuk.dhfs.utils.AutoCloseableNoThrow;
 import com.usatiuk.objects.JData;
 import com.usatiuk.objects.JDataVersionedWrapper;
 import com.usatiuk.objects.JObjectKey;
 import com.usatiuk.objects.snapshot.Snapshot;
 import com.usatiuk.objects.snapshot.SnapshotManager;
-import com.usatiuk.dhfs.utils.AutoCloseableNoThrow;
 import io.quarkus.logging.Log;
 import io.quarkus.runtime.StartupEvent;
 import jakarta.annotation.Priority;
@@ -13,20 +14,22 @@ import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.enterprise.event.Observes;
 import jakarta.enterprise.inject.Instance;
 import jakarta.inject.Inject;
+import jakarta.inject.Singleton;
 import org.apache.commons.lang3.tuple.Pair;

 import java.util.*;
-import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.stream.Stream;

-// Manages all access to com.usatiuk.objects.JData objects.
-// In particular, it serves as a source of truth for what is committed to the backing storage.
-// All data goes through it, it is responsible for transaction atomicity
-// TODO: persistent tx id
@ApplicationScoped
 public class JObjectManager {
    private final List<PreCommitTxHook> _preCommitTxHooks;
+
+    private record CommitHookIterationData(PreCommitTxHook hook,
+                                           Map<JObjectKey, TxRecord.TxObjectRecord<?>> lastWrites,
+                                           Map<JObjectKey, TxRecord.TxObjectRecord<?>> pendingWrites) {
+    }
+
    @Inject
    SnapshotManager snapshotManager;
    @Inject
@@ -57,25 +60,27 @@ public class JObjectManager {

    public Pair<Collection<Runnable>, TransactionHandle> commit(TransactionPrivate tx) {
        verifyReady();
-        var writes = new LinkedHashMap<JObjectKey, TxRecord.TxObjectRecord<?>>();
-        var dependenciesLocked = new LinkedHashMap<JObjectKey, Optional<JDataVersionedWrapper>>();
+        var writes = new HashMap<JObjectKey, TxRecord.TxObjectRecord<?>>();
        Snapshot<JObjectKey, JDataVersionedWrapper> commitSnapshot = null;
-        Map<JObjectKey, TransactionObject<?>> readSet;
-        var toUnlock = new ArrayList<AutoCloseableNoThrow>();
+        Map<JObjectKey, TransactionObject<?>> readSet = null;
+        Collection<AutoCloseableNoThrow> toUnlock = null;

        try {
            try {
                long pendingCount = 0;
-                Map<PreCommitTxHook, Map<JObjectKey, TxRecord.TxObjectRecord<?>>> pendingWrites = Map.ofEntries(
-                        _preCommitTxHooks.stream().map(p -> Pair.of(p, new HashMap<>())).toArray(Pair[]::new)
-                );
-                Map<PreCommitTxHook, Map<JObjectKey, TxRecord.TxObjectRecord<?>>> lastWrites = Map.ofEntries(
-                        _preCommitTxHooks.stream().map(p -> Pair.of(p, new HashMap<>())).toArray(Pair[]::new)
-                );
+                List<CommitHookIterationData> hookIterationData;
+                {
+                    CommitHookIterationData[] hookIterationDataArray = new CommitHookIterationData[_preCommitTxHooks.size()];
+                    for (int i = 0; i < _preCommitTxHooks.size(); i++) {
+                        var hook = _preCommitTxHooks.get(i);
+                        hookIterationDataArray[i] = new CommitHookIterationData(hook, new HashMap<>(), new HashMap<>());
+                    }
+                    hookIterationData = List.of(hookIterationDataArray);
+                }

                for (var n : tx.drainNewWrites()) {
-                    for (var hookPut : _preCommitTxHooks) {
-                        pendingWrites.get(hookPut).put(n.key(), n);
+                    for (var hookPut : hookIterationData) {
+                        hookPut.pendingWrites().put(n.key(), n);
                        pendingCount++;
                    }
                    writes.put(n.key(), n);
@@ -87,9 +92,10 @@ public class JObjectManager {
                // For example, when a hook makes changes to an object, and another hook changes the object before/after it
                // on the next iteration, the first hook should receive the version of the object it had created
                // as the "old" version, and the new version with all the changes after it.
-                do {
-                    for (var hook : _preCommitTxHooks) {
-                        var lastCurHookSeen = lastWrites.get(hook);
+                while (pendingCount > 0) {
+                    for (var hookId : hookIterationData) {
+                        var hook = hookId.hook();
+                        var lastCurHookSeen = hookId.lastWrites();
                        Function<JObjectKey, JData> getPrev =
                                key -> switch (lastCurHookSeen.get(key)) {
                                    case TxRecord.TxObjectRecordWrite<?> write -> write.data();
@@ -100,7 +106,7 @@ public class JObjectManager {
                                    }
                                };

-                        var curIteration = pendingWrites.get(hook);
+                        var curIteration = hookId.pendingWrites();

 //                        Log.trace("Commit iteration with " + curIteration.size() + " records for hook " + hook.getClass());

@@ -127,23 +133,23 @@ public class JObjectManager {
                        curIteration.clear();

                        for (var n : tx.drainNewWrites()) {
-                            for (var hookPut : _preCommitTxHooks) {
-                                if (hookPut == hook) {
+                            for (var hookPut : hookIterationData) {
+                                if (hookPut == hookId) {
                                    lastCurHookSeen.put(n.key(), n);
                                    continue;
                                }
-                                var before = pendingWrites.get(hookPut).put(n.key(), n);
+                                var before = hookPut.pendingWrites().put(n.key(), n);
                                if (before == null)
                                    pendingCount++;
                            }
                            writes.put(n.key(), n);
                        }
                    }
-                } while (pendingCount > 0);
+                }
            } catch (Throwable e) {
                for (var read : tx.reads().entrySet()) {
                    if (read.getValue() instanceof TransactionObjectLocked<?> locked) {
-                        toUnlock.add(locked.lock());
+                        locked.lock().close();
                    }
                }
                throw e;
@@ -152,25 +158,34 @@ public class JObjectManager {
            readSet = tx.reads();

            if (!writes.isEmpty()) {
-                Stream.concat(readSet.keySet().stream(), writes.keySet().stream())
-                        .sorted(Comparator.comparing(JObjectKey::toString))
-                        .forEach(k -> {
-                            var lock = lockManager.lockObject(k);
-                            toUnlock.add(lock);
-                        });
+                toUnlock = new ArrayList<>(readSet.size() + writes.size());
+                ArrayList<JObjectKey> toLock = new ArrayList<>(readSet.size() + writes.size());
+                for (var read : readSet.entrySet()) {
+                    if (read.getValue() instanceof TransactionObjectLocked<?> locked) {
+                        toUnlock.add(locked.lock());
+                    } else {
+                        toLock.add(read.getKey());
+                    }
+                }
+                for (var write : writes.entrySet()) {
+                    toLock.add(write.getKey());
+                }
+                Collections.sort(toLock);
+                for (var key : toLock) {
+                    var lock = lockManager.lockObject(key);
+                    toUnlock.add(lock);
+                }

                commitSnapshot = snapshotManager.createSnapshot();
-            }
-
-            for (var read : readSet.entrySet()) {
-                if (read.getValue() instanceof TransactionObjectLocked<?> locked) {
-                    toUnlock.add(locked.lock());
-                }
-            }
-
-            if (writes.isEmpty()) {
+            } else {
                Log.trace("Committing transaction - no changes");

+                for (var read : readSet.values()) {
+                    if (read instanceof TransactionObjectLocked<?> locked) {
+                        locked.lock().close();
+                    }
+                }
+
                return Pair.of(
                        Stream.concat(
                                tx.getOnCommit().stream(),
@@ -189,24 +204,23 @@ public class JObjectManager {

            if (snapshotId != commitSnapshot.id()) {
                for (var read : readSet.entrySet()) {
-                    dependenciesLocked.put(read.getKey(), commitSnapshot.readObject(read.getKey()));
-                    var dep = dependenciesLocked.get(read.getKey());
+                    var current = commitSnapshot.readObject(read.getKey());

-                    if (dep.isEmpty() != read.getValue().data().isEmpty()) {
+                    if (current.isEmpty() != read.getValue().data().isEmpty()) {
                        Log.tracev("Checking read dependency {0} - not found", read.getKey());
-                        throw new TxCommitException("Serialization hazard: " + dep.isEmpty() + " vs " + read.getValue().data().isEmpty());
+                        throw new TxCommitException("Serialization hazard: " + current.isEmpty() + " vs " + read.getValue().data().isEmpty());
                    }

-                    if (dep.isEmpty()) {
+                    if (current.isEmpty()) {
                        // TODO: Every write gets a dependency due to hooks
                        continue;
 //                    assert false;
-//                    throw new TxCommitException("Serialization hazard: " + dep.isEmpty() + " vs " + read.getValue().data().isEmpty());
+//                    throw new TxCommitException("Serialization hazard: " + dep.isEmpty() + " vs " + read.getValue().value().isEmpty());
                    }

-                    if (dep.get().version() > snapshotId) {
+                    if (current.get().version() > snapshotId) {
                        Log.tracev("Checking dependency {0} - newer than", read.getKey());
-                        throw new TxCommitException("Serialization hazard: " + dep.get().data().key() + " " + dep.get().version() + " vs " + snapshotId);
+                        throw new TxCommitException("Serialization hazard: " + current.get().data().key() + " " + current.get().version() + " vs " + snapshotId);
                    }

                    Log.tracev("Checking dependency {0} - ok with read", read.getKey());
@@ -215,21 +229,7 @@ public class JObjectManager {
                Log.tracev("Skipped dependency checks: no changes");
            }

-            boolean same = snapshotId == commitSnapshot.id();
-
-            var addFlushCallback = snapshotManager.commitTx(
-                    writes.values().stream()
-                            .filter(r -> {
-                                if (!same)
-                                    if (r instanceof TxRecord.TxObjectRecordWrite<?>(JData data)) {
-                                        var dep = dependenciesLocked.get(data.key());
-                                        if (dep.isPresent() && dep.get().version() > snapshotId) {
-                                            Log.trace("Skipping write " + data.key() + " - dependency " + dep.get().version() + " vs " + snapshotId);
-                                            return false;
-                                        }
-                                    }
-                                return true;
-                            }).toList());
+            var addFlushCallback = snapshotManager.commitTx(writes.values());

            for (var callback : tx.getOnFlush()) {
                addFlushCallback.accept(callback);
@@ -247,9 +247,10 @@ public class JObjectManager {
            Log.trace("Error when committing transaction", t);
            throw new TxCommitException(t.getMessage(), t);
        } finally {
-            for (var unlock : toUnlock) {
-                unlock.close();
-            }
+            if (toUnlock != null)
+                for (var unlock : toUnlock) {
+                    unlock.close();
+                }
            if (commitSnapshot != null)
                commitSnapshot.close();
            tx.close();
@@ -265,31 +266,4 @@ public class JObjectManager {
        });
        tx.close();
    }
-
-    //    private class TransactionObjectSourceImpl implements TransactionObjectSource {
-//        private final long _txId;
-//
-//        private TransactionObjectSourceImpl(long txId) {
-//            _txId = txId;
-//        }
-//
-//        @Override
-//        public <T extends JData> TransactionObject<T> get(Class<T> type, JObjectKey key) {
-//            var got = getObj(type, key);
-//            if (got.data().isPresent() && got.data().get().version() > _txId) {
-//                throw new TxCommitException("Serialization race for " + key + ": " + got.data().get().version() + " vs " + _txId);
-//            }
-//            return got;
-//        }
-//
-//        @Override
-//        public <T extends JData> TransactionObject<T> getWriteLocked(Class<T> type, JObjectKey key) {
-//            var got = getObjLock(type, key);
-//            if (got.data().isPresent() && got.data().get().version() > _txId) {
-//                got.lock().close();
-//                throw new TxCommitException("Serialization race for " + key + ": " + got.data().get().version() + " vs " + _txId);
-//            }
-//            return got;
-//        }
-//    }
 }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/LockManager.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/LockManager.java
@@ -6,8 +6,9 @@ import com.usatiuk.dhfs.utils.DataLocker;
 import jakarta.annotation.Nonnull;
 import jakarta.annotation.Nullable;
 import jakarta.enterprise.context.ApplicationScoped;
+import jakarta.inject.Singleton;

-@ApplicationScoped
+@Singleton
 public class LockManager {
    private final DataLocker _objLocker = new DataLocker();

--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/TransactionFactoryImpl.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/TransactionFactoryImpl.java
@@ -7,14 +7,14 @@ import com.usatiuk.objects.iterators.*;
 import com.usatiuk.objects.snapshot.Snapshot;
 import com.usatiuk.objects.snapshot.SnapshotManager;
 import io.quarkus.logging.Log;
-import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.inject.Inject;
+import jakarta.inject.Singleton;
 import org.apache.commons.lang3.tuple.Pair;
 import org.eclipse.microprofile.config.inject.ConfigProperty;

 import java.util.*;

-@ApplicationScoped
+@Singleton
 public class TransactionFactoryImpl implements TransactionFactory {
    @Inject
    SnapshotManager snapshotManager;
@@ -161,20 +161,25 @@ public class TransactionFactoryImpl implements TransactionFactory {
        @Override
        public CloseableKvIterator<JObjectKey, JData> getIterator(IteratorStart start, JObjectKey key) {
            Log.tracev("Getting tx iterator with start={0}, key={1}", start, key);
-            return new ReadTrackingIterator(new TombstoneMergingKvIterator<>("tx", start, key,
+            return new ReadTrackingIterator(TombstoneMergingKvIterator.<JObjectKey, ReadTrackingInternalCrap>of("tx", start, key,
                    (tS, tK) -> new MappingKvIterator<>(new NavigableMapKvIterator<>(_writes, tS, tK),
                            t -> switch (t) {
                                case TxRecord.TxObjectRecordWrite<?> write ->
-                                        new Data<>(new ReadTrackingInternalCrapTx(write.data()));
-                                case TxRecord.TxObjectRecordDeleted deleted -> new Tombstone<>();
+                                        new DataWrapper<>(new ReadTrackingInternalCrapTx(write.data()));
+                                case TxRecord.TxObjectRecordDeleted deleted -> new TombstoneImpl<>();
                                case null, default -> null;
                            }),
                    (tS, tK) -> new MappingKvIterator<>(_snapshot.getIterator(tS, tK),
-                            d -> new Data<ReadTrackingInternalCrap>(new ReadTrackingInternalCrapSource(d)))));
+                            d -> new DataWrapper<ReadTrackingInternalCrap>(new ReadTrackingInternalCrapSource(d)))));
        }

        @Override
        public void put(JData obj) {
+            var read = _readSet.get(obj.key());
+            if (read != null && (read.data().map(JDataVersionedWrapper::data).orElse(null) == obj)) {
+                return;
+            }
+
            _writes.put(obj.key(), new TxRecord.TxObjectRecordWrite<>(obj));
            _newWrites.put(obj.key(), new TxRecord.TxObjectRecordWrite<>(obj));
        }
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/TransactionManager.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/TransactionManager.java
@@ -17,30 +17,27 @@ public interface TransactionManager {
            return supplier.get();
        }

-        begin();
-        T ret;
-        try {
-            ret = supplier.get();
-        } catch (TxCommitException txCommitException) {
-            rollback();
-            if (tries == 0) {
-                Log.error("Transaction commit failed", txCommitException);
-                throw txCommitException;
+        while (true) {
+            begin();
+            boolean commit = false;
+            try {
+                var ret = supplier.get();
+                commit = true;
+                commit();
+                return ret;
+            } catch (TxCommitException txCommitException) {
+                if (!commit)
+                    rollback();
+                if (tries == 0) {
+                    Log.error("Transaction commit failed", txCommitException);
+                    throw txCommitException;
+                }
+                tries--;
+            } catch (Throwable e) {
+                if (!commit)
+                    rollback();
+                throw e;
            }
-            return runTries(supplier, tries - 1);
-        } catch (Throwable e) {
-            rollback();
-            throw e;
-        }
-        try {
-            commit();
-            return ret;
-        } catch (TxCommitException txCommitException) {
-            if (tries == 0) {
-                Log.error("Transaction commit failed", txCommitException);
-                throw txCommitException;
-            }
-            return runTries(supplier, tries - 1);
        }
    }

@@ -55,29 +52,29 @@ public interface TransactionManager {
            };
        }

-        begin();
-        try {
-            fn.apply();
-        } catch (TxCommitException txCommitException) {
-            rollback();
-            if (tries == 0) {
-                Log.error("Transaction commit failed", txCommitException);
-                throw txCommitException;
+        while (true) {
+            begin();
+            boolean commit = false;
+            try {
+                fn.apply();
+                commit = true;
+                var ret = commit();
+                return ret;
+            } catch (TxCommitException txCommitException) {
+                if (!commit)
+                    rollback();
+                if (tries == 0) {
+                    Log.error("Transaction commit failed", txCommitException);
+                    throw txCommitException;
+                }
+                tries--;
+            } catch (Throwable e) {
+                if (!commit)
+                    rollback();
+                throw e;
            }
-            return runTries(fn, tries - 1);
-        } catch (Throwable e) {
-            rollback();
-            throw e;
-        }
-        try {
-            return commit();
-        } catch (TxCommitException txCommitException) {
-            if (tries == 0) {
-                Log.error("Transaction commit failed", txCommitException);
-                throw txCommitException;
-            }
-            return runTries(fn, tries - 1);
        }
+
    }

    default TransactionHandle run(VoidFn fn) {
--- a/dhfs-parent/objects/src/test/java/com/usatiuk/objects/iterators/MergingKvIteratorPbtTest.java
+++ b/dhfs-parent/objects/src/test/java/com/usatiuk/objects/iterators/MergingKvIteratorPbtTest.java
@@ -0,0 +1,262 @@
+package com.usatiuk.objects.iterators;
+
+import net.jqwik.api.*;
+import net.jqwik.api.state.Action;
+import net.jqwik.api.state.ActionChain;
+import org.apache.commons.lang3.tuple.Pair;
+import org.junit.jupiter.api.Assertions;
+
+import java.util.*;
+
+public class MergingKvIteratorPbtTest {
+    static class MergingIteratorModel implements CloseableKvIterator<Integer, Integer> {
+        private final CloseableKvIterator<Integer, Integer> mergedIterator;
+        private final CloseableKvIterator<Integer, Integer> mergingIterator;
+
+        private MergingIteratorModel(List<List<Map.Entry<Integer, Integer>>> pairs, IteratorStart startType, Integer startKey) {
+            TreeMap<Integer, Integer> perfectMerged = new TreeMap<>();
+            for (List<Map.Entry<Integer, Integer>> list : pairs) {
+                for (Map.Entry<Integer, Integer> pair : list) {
+                    perfectMerged.putIfAbsent(pair.getKey(), pair.getValue());
+                }
+            }
+            mergedIterator = new NavigableMapKvIterator<>(perfectMerged, startType, startKey);
+            mergingIterator = new MergingKvIterator<>("test", startType, startKey, pairs.stream().<IterProdFn<Integer, Integer>>map(
+                    list -> (IteratorStart start, Integer key) -> new NavigableMapKvIterator<>(new TreeMap<Integer, Integer>(Map.ofEntries(list.toArray(Map.Entry[]::new))), start, key)
+            ).toList());
+        }
+
+        @Override
+        public Integer peekNextKey() {
+            var mergedKey = mergedIterator.peekNextKey();
+            var mergingKey = mergingIterator.peekNextKey();
+            Assertions.assertEquals(mergedKey, mergingKey);
+            return mergedKey;
+        }
+
+        @Override
+        public void skip() {
+            mergedIterator.skip();
+            mergingIterator.skip();
+        }
+
+        @Override
+        public Integer peekPrevKey() {
+            var mergedKey = mergedIterator.peekPrevKey();
+            var mergingKey = mergingIterator.peekPrevKey();
+            Assertions.assertEquals(mergedKey, mergingKey);
+            return mergedKey;
+        }
+
+        @Override
+        public Pair<Integer, Integer> prev() {
+            var mergedKey = mergedIterator.prev();
+            var mergingKey = mergingIterator.prev();
+            Assertions.assertEquals(mergedKey, mergingKey);
+            return mergedKey;
+        }
+
+        @Override
+        public boolean hasPrev() {
+            var mergedKey = mergedIterator.hasPrev();
+            var mergingKey = mergingIterator.hasPrev();
+            Assertions.assertEquals(mergedKey, mergingKey);
+            return mergedKey;
+        }
+
+        @Override
+        public void skipPrev() {
+            mergedIterator.skipPrev();
+            mergingIterator.skipPrev();
+        }
+
+        @Override
+        public void close() {
+            mergedIterator.close();
+            mergingIterator.close();
+        }
+
+        @Override
+        public boolean hasNext() {
+            var mergedKey = mergedIterator.hasNext();
+            var mergingKey = mergingIterator.hasNext();
+            Assertions.assertEquals(mergedKey, mergingKey);
+            return mergedKey;
+        }
+
+        @Override
+        public Pair<Integer, Integer> next() {
+            var mergedKey = mergedIterator.next();
+            var mergingKey = mergingIterator.next();
+            Assertions.assertEquals(mergedKey, mergingKey);
+            return mergedKey;
+        }
+    }
+
+    static class PeekNextKeyAction extends Action.JustMutate<MergingIteratorModel> {
+        @Override
+        public void mutate(MergingIteratorModel state) {
+            state.peekNextKey();
+        }
+
+        @Override
+        public boolean precondition(MergingIteratorModel state) {
+            return state.hasNext();
+        }
+
+        @Override
+        public String description() {
+            return "Peek next key";
+        }
+    }
+
+    static class SkipAction extends Action.JustMutate<MergingIteratorModel> {
+        @Override
+        public void mutate(MergingIteratorModel state) {
+            state.skip();
+        }
+
+        @Override
+        public boolean precondition(MergingIteratorModel state) {
+            return state.hasNext();
+        }
+
+        @Override
+        public String description() {
+            return "Skip next key";
+        }
+    }
+
+    static class PeekPrevKeyAction extends Action.JustMutate<MergingIteratorModel> {
+        @Override
+        public void mutate(MergingIteratorModel state) {
+            state.peekPrevKey();
+        }
+
+        @Override
+        public boolean precondition(MergingIteratorModel state) {
+            return state.hasPrev();
+        }
+
+        @Override
+        public String description() {
+            return "Peek prev key";
+        }
+    }
+
+    static class SkipPrevAction extends Action.JustMutate<MergingIteratorModel> {
+        @Override
+        public void mutate(MergingIteratorModel state) {
+            state.skipPrev();
+        }
+
+        @Override
+        public boolean precondition(MergingIteratorModel state) {
+            return state.hasPrev();
+        }
+
+        @Override
+        public String description() {
+            return "Skip prev key";
+        }
+    }
+
+    static class PrevAction extends Action.JustMutate<MergingIteratorModel> {
+        @Override
+        public void mutate(MergingIteratorModel state) {
+            state.prev();
+        }
+
+        @Override
+        public boolean precondition(MergingIteratorModel state) {
+            return state.hasPrev();
+        }
+
+        @Override
+        public String description() {
+            return "Prev key";
+        }
+    }
+
+    static class NextAction extends Action.JustMutate<MergingIteratorModel> {
+        @Override
+        public void mutate(MergingIteratorModel state) {
+            state.next();
+        }
+
+        @Override
+        public boolean precondition(MergingIteratorModel state) {
+            return state.hasNext();
+        }
+
+        @Override
+        public String description() {
+            return "Next key";
+        }
+    }
+
+    static class HasNextAction extends Action.JustMutate<MergingIteratorModel> {
+        @Override
+        public void mutate(MergingIteratorModel state) {
+            state.hasNext();
+        }
+
+        @Override
+        public boolean precondition(MergingIteratorModel state) {
+            return true;
+        }
+
+        @Override
+        public String description() {
+            return "Has next key";
+        }
+    }
+
+    static class HasPrevAction extends Action.JustMutate<MergingIteratorModel> {
+        @Override
+        public void mutate(MergingIteratorModel state) {
+            state.hasPrev();
+        }
+
+        @Override
+        public boolean precondition(MergingIteratorModel state) {
+            return true;
+        }
+
+        @Override
+        public String description() {
+            return "Has prev key";
+        }
+    }
+
+    @Property
+    public void checkMergingIterator(@ForAll("actions") ActionChain<MergingIteratorModel> actions) {
+        actions.run();
+    }
+
+    @Provide
+    Arbitrary<ActionChain<MergingIteratorModel>> actions(@ForAll("lists") List<List<Map.Entry<Integer, Integer>>> list,
+                                                         @ForAll IteratorStart iteratorStart, @ForAll("startKey") Integer startKey) {
+        return ActionChain.startWith(() -> new MergingIteratorModel(list, iteratorStart, startKey))
+                .withAction(new NextAction())
+                .withAction(new PeekNextKeyAction())
+                .withAction(new SkipAction())
+                .withAction(new PeekPrevKeyAction())
+                .withAction(new SkipPrevAction())
+                .withAction(new PrevAction())
+                .withAction(new HasNextAction())
+                .withAction(new HasPrevAction());
+    }
+
+    @Provide
+    Arbitrary<List<List<Map.Entry<Integer, Integer>>>> lists() {
+        return Arbitraries.entries(Arbitraries.integers().between(-50, 50), Arbitraries.integers().between(-50, 50))
+                .list().uniqueElements(Map.Entry::getKey).ofMinSize(0).ofMaxSize(20)
+                .list().ofMinSize(1).ofMaxSize(5);
+    }
+
+    @Provide
+    Arbitrary<Integer> startKey() {
+        return Arbitraries.integers().between(-51, 51);
+    }
+}
--- a/dhfs-parent/pom.xml
+++ b/dhfs-parent/pom.xml
@@ -16,7 +16,6 @@
        <module>dhfs-fuse</module>
        <module>dhfs-app</module>
        <module>kleppmanntree</module>
-        <module>supportlib</module>
        <module>objects</module>
        <module>utils</module>
    </modules>
@@ -36,13 +35,6 @@
        <dhfs.native-libs-dir>${project.parent.build.outputDirectory}/native</dhfs.native-libs-dir>
    </properties>

-    <repositories>
-        <repository>
-            <id>jitpack.io</id>
-            <url>https://jitpack.io</url>
-        </repository>
-    </repositories>
-
    <dependencyManagement>
        <dependencies>
            <dependency>
@@ -52,6 +44,12 @@
                <type>pom</type>
                <scope>import</scope>
            </dependency>
+            <dependency>
+                <groupId>net.jqwik</groupId>
+                <artifactId>jqwik</artifactId>
+                <version>1.9.2</version>
+                <scope>test</scope>
+            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
@@ -116,9 +114,6 @@
                    <systemPropertyVariables>
                        <java.util.logging.manager>org.jboss.logmanager.LogManager</java.util.logging.manager>
                        <maven.home>${maven.home}</maven.home>
-                        <com.usatiuk.dhfs.supportlib.native-path>
-                            ${dhfs.native-libs-dir}
-                        </com.usatiuk.dhfs.supportlib.native-path>
                    </systemPropertyVariables>
                    <argLine>
                        --add-exports java.base/sun.nio.ch=ALL-UNNAMED
@@ -149,6 +144,7 @@
                        </native.image.path>
                        <java.util.logging.manager>org.jboss.logmanager.LogManager</java.util.logging.manager>
                        <buildDirectory>${project.build.directory}</buildDirectory>
+                        <lazyFsPath>${project.basedir}/../../thirdparty/lazyfs/lazyfs/lazyfs</lazyFsPath>
                        <nativeLibsDirectory>${dhfs.native-libs-dir}</nativeLibsDirectory>
                        <maven.home>${maven.home}</maven.home>
                    </systemPropertyVariables>
@@ -186,7 +182,6 @@
                    --initialize-at-run-time=com.usatiuk.dhfs.utils.DataLocker$Lock,
                    --initialize-at-run-time=com.usatiuk.objects.stores.LmdbObjectPersistentStore$LmdbKvIterator,
                    --initialize-at-run-time=com.usatiuk.objects.stores.LmdbObjectPersistentStore,
-                    --initialize-at-run-time=com.usatiuk.dhfs.supportlib.UninitializedByteBuffer,
                    --initialize-at-run-time=com.google.protobuf.UnsafeUtil
                </quarkus.native.additional-build-args>
            </properties>
--- a/dhfs-parent/supportlib/pom.xml
+++ b/dhfs-parent/supportlib/pom.xml
@@ -1,114 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xmlns="http://maven.apache.org/POM/4.0.0"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <modelVersion>4.0.0</modelVersion>
-    <parent>
-        <groupId>com.usatiuk.dhfs</groupId>
-        <artifactId>parent</artifactId>
-        <version>1.0-SNAPSHOT</version>
-    </parent>
-
-    <artifactId>supportlib</artifactId>
-
-    <properties>
-        <cmake.download>false</cmake.download>
-    </properties>
-
-    <dependencies>
-        <dependency>
-            <groupId>org.apache.commons</groupId>
-            <artifactId>commons-lang3</artifactId>
-        </dependency>
-    </dependencies>
-
-    <build>
-        <plugins>
-            <plugin>
-                <artifactId>exec-maven-plugin</artifactId>
-                <groupId>org.codehaus.mojo</groupId>
-                <version>3.4.1</version>
-                <executions>
-                    <execution>
-                        <id>CMake Configure</id>
-                        <phase>generate-sources</phase>
-                        <goals>
-                            <goal>exec</goal>
-                        </goals>
-                        <configuration>
-                            <executable>
-                                ${project.parent.basedir}/../libdhfs_support/builder/cross-build.sh
-                            </executable>
-                            <arguments>
-                                <argument>configure</argument>
-                                <argument>${project.build.outputDirectory}/native-build</argument>
-                                <argument>${dhfs.native-libs-dir}</argument>
-                            </arguments>
-                        </configuration>
-                    </execution>
-                    <execution>
-                        <id>CMake Build</id>
-                        <phase>compile</phase>
-                        <goals>
-                            <goal>exec</goal>
-                        </goals>
-                        <configuration>
-                            <executable>
-                                ${project.parent.basedir}/../libdhfs_support/builder/cross-build.sh
-                            </executable>
-                            <arguments>
-                                <argument>build</argument>
-                                <argument>${project.build.outputDirectory}/native-build</argument>
-                                <argument>${dhfs.native-libs-dir}</argument>
-                            </arguments>
-                        </configuration>
-                    </execution>
-                </executions>
-            </plugin>
-            <plugin>
-                <groupId>com.googlecode.cmake-maven-project</groupId>
-                <artifactId>cmake-maven-plugin</artifactId>
-                <version>3.30.2-b1</version>
-                <executions>
-                    <execution>
-                        <id>cmake-generate</id>
-                        <goals>
-                            <goal>generate</goal>
-                        </goals>
-                        <configuration>
-                            <sourcePath>
-                                ${project.parent.basedir}/../libdhfs_support
-                            </sourcePath>
-                            <targetPath>
-                                ${project.build.outputDirectory}/native-build-local
-                            </targetPath>
-                            <options>
-                                <option>
-                                    -DJAVA_HOME=${java.home}
-                                </option>
-                                <option>
-                                    -DDHFS_LIB_INSTALL=${dhfs.native-libs-dir}
-                                </option>
-                            </options>
-                        </configuration>
-                    </execution>
-                    <execution>
-                        <id>cmake-compile</id>
-                        <goals>
-                            <goal>compile</goal>
-                        </goals>
-                        <configuration>
-                            <target>
-                                install
-                            </target>
-                            <projectDirectory>
-                                ${project.build.outputDirectory}/native-build-local
-                            </projectDirectory>
-                        </configuration>
-                    </execution>
-                </executions>
-            </plugin>
-        </plugins>
-    </build>
-
-</project>
--- a/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsNativeLibFinder.java
+++ b/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsNativeLibFinder.java
@@ -1,15 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-import java.nio.file.Path;
-
-class DhfsNativeLibFinder {
-    static private final String LibName = "libdhfs_support";
-
-    static Path getLibPath() {
-        var override = System.getProperty("com.usatiuk.dhfs.supportlib.native-path-override");
-        if (override != null)
-            return Path.of(override);
-        return Path.of(System.getProperty("com.usatiuk.dhfs.supportlib.native-path"))
-                .resolve(SysUtils.getLibPlatform() + "-" + SysUtils.getLibArch()).resolve(LibName + "." + SysUtils.getLibExtension());
-    }
-}
--- a/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupport.java
+++ b/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupport.java
@@ -1,35 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-import java.nio.ByteBuffer;
-import java.util.logging.Logger;
-
-public class DhfsSupport {
-    public static final int PAGE_SIZE;
-    private static final Logger LOGGER = Logger.getLogger(DhfsSupport.class.getName());
-    private static final DhfsSupportImpl IMPLEMENTATION;
-
-    static {
-        DhfsSupportImpl tmp;
-        try {
-            System.load(DhfsNativeLibFinder.getLibPath().toAbsolutePath().toString());
-            tmp = new DhfsSupportImplNative();
-        } catch (Throwable e) {
-            LOGGER.warning("Failed to load native libraries, using fallback: \n" + e);
-            tmp = new DhfsSupportImplFallback();
-        }
-        IMPLEMENTATION = tmp;
-        PAGE_SIZE = getPageSizeInternal();
-    }
-
-    static long allocateUninitializedByteBuffer(ByteBuffer[] bb, int size) {
-        return IMPLEMENTATION.allocateUninitializedByteBuffer(bb, size);
-    }
-
-    static void releaseByteBuffer(long token) {
-        IMPLEMENTATION.releaseByteBuffer(token);
-    }
-
-    private static int getPageSizeInternal() {
-        return IMPLEMENTATION.getPageSizeInternal();
-    }
-}
--- a/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportImpl.java
+++ b/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportImpl.java
@@ -1,11 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-import java.nio.ByteBuffer;
-
-interface DhfsSupportImpl {
-    long allocateUninitializedByteBuffer(ByteBuffer[] bb, int size);
-
-    void releaseByteBuffer(long token);
-
-    int getPageSizeInternal();
-}
--- a/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportImplFallback.java
+++ b/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportImplFallback.java
@@ -1,21 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-import java.nio.ByteBuffer;
-
-class DhfsSupportImplFallback implements DhfsSupportImpl {
-    @Override
-    public long allocateUninitializedByteBuffer(ByteBuffer[] bb, int size) {
-        bb[0] = ByteBuffer.allocateDirect(size);
-        return -1;
-    }
-
-    @Override
-    public void releaseByteBuffer(long token) {
-        // GC
-    }
-
-    @Override
-    public int getPageSizeInternal() {
-        return 4096; // FIXME:?
-    }
-}
--- a/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportImplNative.java
+++ b/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportImplNative.java
@@ -1,20 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-import java.nio.ByteBuffer;
-
-class DhfsSupportImplNative implements DhfsSupportImpl {
-    @Override
-    public long allocateUninitializedByteBuffer(ByteBuffer[] bb, int size) {
-        return DhfsSupportNative.allocateUninitializedByteBuffer(bb, size);
-    }
-
-    @Override
-    public void releaseByteBuffer(long token) {
-        DhfsSupportNative.releaseByteBuffer(token);
-    }
-
-    @Override
-    public int getPageSizeInternal() {
-        return DhfsSupportNative.PAGE_SIZE;
-    }
-}
--- a/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportNative.java
+++ b/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportNative.java
@@ -1,20 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-
-import java.nio.ByteBuffer;
-
-
-class DhfsSupportNative {
-    static public final int PAGE_SIZE;
-
-    static {
-        System.load(DhfsNativeLibFinder.getLibPath().toAbsolutePath().toString());
-        PAGE_SIZE = getPageSizeInternal();
-    }
-
-    static native long allocateUninitializedByteBuffer(ByteBuffer[] bb, int size);
-
-    static native void releaseByteBuffer(long token);
-
-    private static native int getPageSizeInternal();
-}
--- a/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/SysUtils.java
+++ b/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/SysUtils.java
@@ -1,43 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-import org.apache.commons.lang3.SystemUtils;
-
-class SysUtils {
-    static String getLibPlatform() {
-        if (SystemUtils.IS_OS_MAC) {
-            return "Darwin";
-        } else if (SystemUtils.IS_OS_LINUX) {
-            return "Linux";
-        } else {
-            throw new IllegalStateException("Unsupported OS: " + SystemUtils.OS_NAME);
-        }
-    }
-
-    static String getLibExtension() {
-        if (SystemUtils.IS_OS_MAC) {
-            return "dylib";
-        } else if (SystemUtils.IS_OS_LINUX) {
-            return "so";
-        } else {
-            throw new IllegalStateException("Unsupported OS: " + SystemUtils.OS_NAME);
-        }
-    }
-
-    static String getLibArch() {
-        if (SystemUtils.IS_OS_MAC) {
-            return switch (SystemUtils.OS_ARCH) {
-                case "aarch64" -> "arm64";
-                default -> throw new IllegalStateException("Unsupported architecture: " + SystemUtils.OS_ARCH);
-            };
-        } else if (SystemUtils.IS_OS_LINUX) {
-            return switch (SystemUtils.OS_ARCH) {
-                case "aarch64" -> "aarch64";
-                case "amd64" -> "x86_64";
-                default -> throw new IllegalStateException("Unsupported architecture: " + SystemUtils.OS_ARCH);
-            };
-        } else {
-            throw new IllegalStateException("Unsupported OS: " + SystemUtils.OS_NAME);
-        }
-
-    }
-}
--- a/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/UninitializedByteBuffer.java
+++ b/dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/UninitializedByteBuffer.java
@@ -1,32 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-import java.lang.ref.Cleaner;
-import java.nio.ByteBuffer;
-import java.util.logging.Logger;
-
-public class UninitializedByteBuffer {
-    private static final Cleaner CLEANER = Cleaner.create();
-    private static final Logger LOGGER = Logger.getLogger(UninitializedByteBuffer.class.getName());
-
-    public static ByteBuffer allocateUninitialized(int size) {
-        try {
-            if (size < DhfsSupport.PAGE_SIZE)
-                return ByteBuffer.allocateDirect(size);
-
-            var bb = new ByteBuffer[1];
-            long token = DhfsSupport.allocateUninitializedByteBuffer(bb, size);
-            var ret = bb[0];
-            CLEANER.register(ret, () -> {
-                try {
-                    DhfsSupport.releaseByteBuffer(token);
-                } catch (Throwable e) {
-                    LOGGER.severe("Error releasing buffer: " + e);
-                    System.exit(-1);
-                }
-            });
-            return ret;
-        } catch (OutOfMemoryError e) {
-            return ByteBuffer.allocate(size);
-        }
-    }
-}
--- a/dhfs-parent/sync-base/pom.xml
+++ b/dhfs-parent/sync-base/pom.xml
@@ -72,26 +72,6 @@
            <artifactId>quarkus-junit5</artifactId>
            <scope>test</scope>
        </dependency>
-        <dependency>
-            <groupId>com.github.SerCeMan</groupId>
-            <artifactId>jnr-fuse</artifactId>
-            <version>44ed40f8ce</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-ffi</artifactId>
-            <version>2.2.16</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-posix</artifactId>
-            <version>3.1.19</version>
-        </dependency>
-        <dependency>
-            <groupId>com.github.jnr</groupId>
-            <artifactId>jnr-constants</artifactId>
-            <version>0.10.4</version>
-        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
@@ -127,11 +107,6 @@
            <artifactId>kleppmanntree</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
-        <dependency>
-            <groupId>com.usatiuk.dhfs</groupId>
-            <artifactId>supportlib</artifactId>
-            <version>1.0-SNAPSHOT</version>
-        </dependency>
        <dependency>
            <groupId>com.usatiuk.dhfs</groupId>
            <artifactId>objects</artifactId>
--- a/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/RemoteObjectDataWrapper.java
+++ b/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/RemoteObjectDataWrapper.java
@@ -6,30 +6,27 @@ import org.pcollections.PCollection;

 import java.util.Collection;

-public record RemoteObjectDataWrapper<T extends JDataRemote>(PCollection<JDataRef> refsFrom,
-                                                             boolean frozen,
-                                                             T data) implements JDataRefcounted {
+public record RemoteObjectDataWrapper<T extends JDataRemote>(
+        JObjectKey key,
+        PCollection<JDataRef> refsFrom,
+        boolean frozen,
+        T data) implements JDataRefcounted {
    public RemoteObjectDataWrapper(T data) {
-        this(HashTreePSet.empty(), false, data);
+        this(RemoteObjectMeta.ofDataKey(data.key()), HashTreePSet.empty(), false, data);
    }

    @Override
    public RemoteObjectDataWrapper<T> withRefsFrom(PCollection<JDataRef> refs) {
-        return new RemoteObjectDataWrapper<>(refs, frozen, data);
+        return new RemoteObjectDataWrapper<>(key, refs, frozen, data);
    }

    @Override
    public RemoteObjectDataWrapper<T> withFrozen(boolean frozen) {
-        return new RemoteObjectDataWrapper<>(refsFrom, frozen, data);
+        return new RemoteObjectDataWrapper<>(key, refsFrom, frozen, data);
    }

    public RemoteObjectDataWrapper<T> withData(T data) {
-        return new RemoteObjectDataWrapper<>(refsFrom, frozen, data);
-    }
-
-    @Override
-    public JObjectKey key() {
-        return RemoteObjectMeta.ofDataKey(data.key());
+        return new RemoteObjectDataWrapper<>(key, refsFrom, frozen, data);
    }

    @Override
--- a/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/RemoteObjectMeta.java
+++ b/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/RemoteObjectMeta.java
@@ -41,7 +41,7 @@ public record RemoteObjectMeta(PCollection<JDataRef> refsFrom, boolean frozen,
    }

    public static JObjectKey ofDataKey(JObjectKey key) {
-        return JObjectKey.of("data_" + key.value());
+        return JObjectKey.of(key.value() + "_data");
    }

    @Override
--- a/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/RemoteTransaction.java
+++ b/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/RemoteTransaction.java
@@ -9,12 +9,13 @@ import com.usatiuk.objects.transaction.Transaction;
 import io.quarkus.logging.Log;
 import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.inject.Inject;
+import jakarta.inject.Singleton;
 import org.apache.commons.lang3.mutable.MutableObject;
 import org.pcollections.HashTreePSet;

 import java.util.Optional;

-@ApplicationScoped
+@Singleton
 public class RemoteTransaction {
    @Inject
    Transaction curTx;
--- a/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/jmap/JMapEntry.java
+++ b/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/jmap/JMapEntry.java
@@ -3,11 +3,11 @@ package com.usatiuk.dhfs.jmap;
 import com.usatiuk.objects.JData;
 import com.usatiuk.objects.JObjectKey;

-public record JMapEntry<K extends JMapKey>(JObjectKey holder,
+public record JMapEntry<K extends JMapKey>(JObjectKey key,
+                                           JObjectKey holder,
                                           K selfKey,
                                           JObjectKey ref) implements JData {
-    @Override
-    public JObjectKey key() {
-        return JMapHelper.makeKey(holder, selfKey);
+    public JMapEntry(JObjectKey holder, K selfKey, JObjectKey ref) {
+        this(JMapHelper.makeKey(holder, selfKey), holder, selfKey, ref);
    }
 }
--- a/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/jmap/JMapHelper.java
+++ b/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/jmap/JMapHelper.java
@@ -7,11 +7,12 @@ import com.usatiuk.objects.transaction.Transaction;
 import io.quarkus.logging.Log;
 import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.inject.Inject;
+import jakarta.inject.Singleton;

 import java.util.ArrayList;
 import java.util.Optional;

-@ApplicationScoped
+@Singleton
 public class JMapHelper {
    @Inject
    Transaction curTx;
--- a/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/repository/PersistentPeerDataService.java
+++ b/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/repository/PersistentPeerDataService.java
@@ -1,11 +1,13 @@
 package com.usatiuk.dhfs.repository;

+import com.google.protobuf.ByteString;
 import com.usatiuk.dhfs.PeerId;
 import com.usatiuk.dhfs.ShutdownChecker;
 import com.usatiuk.dhfs.repository.peerdiscovery.IpPeerAddress;
 import com.usatiuk.dhfs.repository.peerdiscovery.PeerAddressType;
 import com.usatiuk.dhfs.repository.peersync.PeerInfoService;
 import com.usatiuk.dhfs.repository.peertrust.PeerTrustManager;
+import com.usatiuk.dhfs.utils.SerializationHelper;
 import com.usatiuk.objects.transaction.Transaction;
 import com.usatiuk.objects.transaction.TransactionManager;
 import io.quarkus.logging.Log;
@@ -64,8 +66,8 @@ public class PersistentPeerDataService {
            var selfData = curTx.get(PersistentRemoteHostsData.class, PersistentRemoteHostsData.KEY).orElse(null);
            if (selfData != null) {
                _selfUuid = selfData.selfUuid();
-                _selfCertificate = selfData.selfCertificate();
-                _selfKeyPair = selfData.selfKeyPair();
+                _selfCertificate = CertificateTools.certFromBytes(selfData.selfCertificate().toByteArray());
+                _selfKeyPair = SerializationHelper.deserialize(selfData.selfKeyPair().toByteArray());
                return;
            } else {
                try {
@@ -74,7 +76,7 @@ public class PersistentPeerDataService {
                    _selfKeyPair = CertificateTools.generateKeyPair();
                    _selfCertificate = CertificateTools.generateCertificate(_selfKeyPair, _selfUuid.toString());

-                    curTx.put(new PersistentRemoteHostsData(_selfUuid, _selfCertificate, _selfKeyPair, HashTreePSet.empty(), HashTreePMap.empty()));
+                    curTx.put(new PersistentRemoteHostsData(_selfUuid, ByteString.copyFrom(_selfCertificate.getEncoded()), SerializationHelper.serialize(_selfKeyPair), HashTreePSet.empty(), HashTreePMap.empty()));
                    peerInfoService.putPeer(_selfUuid, _selfCertificate.getEncoded());
                } catch (CertificateEncodingException e) {
                    throw new RuntimeException(e);
--- a/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/repository/PersistentRemoteHostsData.java
+++ b/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/repository/PersistentRemoteHostsData.java
@@ -1,5 +1,6 @@
 package com.usatiuk.dhfs.repository;

+import com.google.protobuf.ByteString;
 import com.usatiuk.dhfs.PeerId;
 import com.usatiuk.dhfs.repository.peerdiscovery.IpPeerAddress;
 import com.usatiuk.objects.JData;
@@ -12,8 +13,8 @@ import java.security.KeyPair;
 import java.security.cert.X509Certificate;

 public record PersistentRemoteHostsData(PeerId selfUuid,
-                                        X509Certificate selfCertificate,
-                                        KeyPair selfKeyPair,
+                                        ByteString selfCertificate,
+                                        ByteString selfKeyPair,
                                        PSet<PeerId> initialSyncDone,
                                        PMap<PeerId, IpPeerAddress> persistentPeerAddress) implements JData, Serializable {
    public static final JObjectKey KEY = JObjectKey.of("self_peer_data");
--- a/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/repository/invalidation/DeferredInvalidationQueueService.java
+++ b/dhfs-parent/sync-base/src/main/java/com/usatiuk/dhfs/repository/invalidation/DeferredInvalidationQueueService.java
@@ -36,7 +36,11 @@ public class DeferredInvalidationQueueService implements PeerConnectedEventListe
        Log.info("Initializing with root " + dataRoot);
        if (Paths.get(dataRoot).resolve(dataFileName).toFile().exists()) {
            Log.info("Reading invalidation queue");
-            _persistentData = SerializationHelper.deserialize(Files.readAllBytes(Paths.get(dataRoot).resolve(dataFileName)));
+            try {
+                _persistentData = SerializationHelper.deserialize(Files.readAllBytes(Paths.get(dataRoot).resolve(dataFileName)));
+            } catch (Exception e) {
+                Log.error("Error reading invalidation queue", e);
+            }
        }
    }

--- a/dhfs-parent/sync-base/src/test/resources/application.properties
+++ b/dhfs-parent/sync-base/src/test/resources/application.properties
@@ -5,7 +5,6 @@ dhfs.objects.ref_verification=true
 dhfs.objects.deletion.delay=0
 quarkus.log.category."com.usatiuk.dhfs".level=TRACE
 quarkus.log.category."com.usatiuk.dhfs".min-level=TRACE
-quarkus.class-loading.parent-first-artifacts=com.usatiuk.dhfs:supportlib
 quarkus.http.test-port=0
 quarkus.http.test-ssl-port=0
 dhfs.local-discovery=false
--- a/dhfs-parent/utils/src/main/java/com/usatiuk/dhfs/utils/DataLocker.java
+++ b/dhfs-parent/utils/src/main/java/com/usatiuk/dhfs/utils/DataLocker.java
@@ -15,57 +15,47 @@ public class DataLocker {
    @Nonnull
    public AutoCloseableNoThrow lock(Object data) {
        while (true) {
+            var newTag = new LockTag();
+            var oldTag = _locks.putIfAbsent(data, newTag);
+            if (oldTag == null) {
+                return new Lock(data, newTag);
+            }
            try {
-                var tag = _locks.get(data);
-                if (tag != null) {
-                    synchronized (tag) {
-                        while (!tag.released) {
-                            if (tag.owner == Thread.currentThread()) {
-                                return DUMMY_LOCK;
-                            }
-                            tag.wait();
+                synchronized (oldTag) {
+                    while (!oldTag.released) {
+                        if (oldTag.owner == Thread.currentThread()) {
+                            return DUMMY_LOCK;
+                        }
+                        oldTag.wait();
 //                            tag.wait(4000L);
 //                            if (!tag.released) {
 //                                System.out.println("Timeout waiting for lock: " + data);
 //                                System.exit(1);
 //                                throw new InterruptedException();
 //                            }
-                        }
-                        continue;
                    }
                }
            } catch (InterruptedException ignored) {
            }
-
-            var newTag = new LockTag();
-            var oldTag = _locks.putIfAbsent(data, newTag);
-            if (oldTag == null) {
-                return new Lock(data, newTag);
-            }
        }
    }

    @Nullable
    public AutoCloseableNoThrow tryLock(Object data) {
        while (true) {
-            var tag = _locks.get(data);
-            if (tag != null) {
-                synchronized (tag) {
-                    if (!tag.released) {
-                        if (tag.owner == Thread.currentThread()) {
-                            return DUMMY_LOCK;
-                        }
-                        return null;
-                    }
-                    continue;
-                }
-            }
-
            var newTag = new LockTag();
            var oldTag = _locks.putIfAbsent(data, newTag);
            if (oldTag == null) {
                return new Lock(data, newTag);
            }
+            synchronized (oldTag) {
+                if (!oldTag.released) {
+                    if (oldTag.owner == Thread.currentThread()) {
+                        return DUMMY_LOCK;
+                    }
+                    return null;
+                }
+            }
        }
    }

@@ -83,11 +73,11 @@ public class DataLocker {
        public Lock(Object key, LockTag tag) {
            _key = key;
            _tag = tag;
-            CLEANER.register(this, () -> {
-                if (!tag.released) {
-                    Log.error("Lock collected without release: " + key);
-                }
-            });
+//            CLEANER.register(this, () -> {
+//                if (!tag.released) {
+//                    Log.error("Lock collected without release: " + key);
+//                }
+//            });
        }

        @Override
--- a/dhfs-parent/utils/src/test/java/com/usatiuk/dhfs/utils/HashSetDelayedBlockingQueueTest.java
+++ b/dhfs-parent/utils/src/test/java/com/usatiuk/dhfs/utils/HashSetDelayedBlockingQueueTest.java
@@ -45,7 +45,7 @@ public class HashSetDelayedBlockingQueueTest {
        queue.add("hello!");
        Assertions.assertEquals("hello!", queue.get());
        var gotTime = System.currentTimeMillis();
-        Assertions.assertTrue((gotTime - curTime) <= 10);
+        Assertions.assertTrue((gotTime - curTime) <= 50);
    }

    @Test
--- a/dockerentry.sh
+++ b/dockerentry.sh
@@ -14,7 +14,6 @@ exec java \
    -Ddhfs.fuse.root=/dhfs_root_fuse \
    -Dquarkus.http.host=0.0.0.0 \
    -Ddhfs.objects.ref_verification=false \
-    -Dcom.usatiuk.dhfs.supportlib.native-path=/usr/src/app/native-libs \
    -Dquarkus.log.category.\"com.usatiuk.dhfs\".level=$DHFS_LOGLEVEL \
    "$@" \
    -jar quarkus-run.jar
--- a/libdhfs_support/.gitignore
+++ b/libdhfs_support/.gitignore
@@ -1,83 +0,0 @@
-.DS_Store
-/toolchain
-/cmake-build-debug
-/sysroot
-/mvn-build
-
-# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
-# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
-
-# User-specific stuff
-.idea/**/workspace.xml
-.idea/**/tasks.xml
-.idea/**/usage.statistics.xml
-.idea/**/dictionaries
-.idea/**/shelf
-
-# AWS User-specific
-.idea/**/aws.xml
-
-# Generated files
-.idea/**/contentModel.xml
-
-# Sensitive or high-churn files
-.idea/**/dataSources/
-.idea/**/dataSources.ids
-.idea/**/dataSources.local.xml
-.idea/**/sqlDataSources.xml
-.idea/**/dynamic.xml
-.idea/**/uiDesigner.xml
-.idea/**/dbnavigator.xml
-
-# Gradle
-.idea/**/gradle.xml
-.idea/**/libraries
-
-# Gradle and Maven with auto-import
-# When using Gradle or Maven with auto-import, you should exclude module files,
-# since they will be recreated, and may cause churn.  Uncomment if using
-# auto-import.
-# .idea/artifacts
-# .idea/compiler.xml
-# .idea/jarRepositories.xml
-# .idea/modules.xml
-# .idea/*.iml
-# .idea/modules
-# *.iml
-# *.ipr
-
-# CMake
-cmake-build-*/
-
-# Mongo Explorer plugin
-.idea/**/mongoSettings.xml
-
-# File-based project format
-*.iws
-
-# IntelliJ
-out/
-
-# mpeltonen/sbt-idea plugin
-.idea_modules/
-
-# JIRA plugin
-atlassian-ide-plugin.xml
-
-# Cursive Clojure plugin
-.idea/replstate.xml
-
-# SonarLint plugin
-.idea/sonarlint/
-
-# Crashlytics plugin (for Android Studio and IntelliJ)
-com_crashlytics_export_strings.xml
-crashlytics.properties
-crashlytics-build.properties
-fabric.properties
-
-# Editor-based Rest Client
-.idea/httpRequests
-
-# Android studio 3.1+ serialized cache file
-.idea/caches/build_file_checksums.ser
--- a/libdhfs_support/CMakeLists.txt
+++ b/libdhfs_support/CMakeLists.txt
@@ -1,39 +0,0 @@
-cmake_minimum_required(VERSION 3.24)
-project(libdhfs_support CXX)
-
-if (CMAKE_BUILD_TYPE STREQUAL "Debug")
-    if (NOT SANITIZE)
-        set(SANITIZE YES)
-    endif ()
-endif ()
-
-include(CheckCXXCompilerFlag)
-
-if (SANITIZE STREQUAL "YES")
-    message(STATUS "Enabling sanitizers!")
-    add_compile_options(-Werror -Wall -Wextra -pedantic -Wshadow -Wformat=2 -Wfloat-equal -D_GLIBCXX_DEBUG -Wconversion)
-    check_cxx_compiler_flag(-fsanitize-trap=all CAN_TRAP)
-    if (CAN_TRAP)
-        add_compile_options(-fsanitize=undefined -fsanitize-trap=all -fno-sanitize-recover)
-        add_link_options(-fsanitize=undefined -fsanitize-trap=all -fno-sanitize-recover)
-    else ()
-        message(WARNING "Sanitizers not supported!")
-    endif ()
-endif ()
-
-if (CMAKE_BUILD_TYPE STREQUAL "Release")
-    add_compile_options(-flto)
-    add_link_options(-flto)
-endif ()
-
-if (NOT CMAKE_BUILD_TYPE STREQUAL "Debug")
-    add_compile_options(-O3)
-    add_link_options(-O3)
-endif ()
-
-message(STATUS "Build type: ${CMAKE_BUILD_TYPE}")
-
-set(CMAKE_POSITION_INDEPENDENT_CODE ON)
-
-add_subdirectory(helpers)
-add_subdirectory(DhfsSupportNative)
--- a/libdhfs_support/DhfsSupportNative/CMakeLists.txt
+++ b/libdhfs_support/DhfsSupportNative/CMakeLists.txt
@@ -1,26 +0,0 @@
-set(CMAKE_CXX_STANDARD 17)
-
-find_package(JNI REQUIRED COMPONENTS JVM)
-find_package(Java REQUIRED)
-include(UseJava)
-
-add_jar(DhfsSupportNative
-        "${PROJECT_SOURCE_DIR}/../dhfs-parent/supportlib/src/main/java/com/usatiuk/dhfs/supportlib/DhfsSupportNative.java"
-        "LibPathDummy.java"
-        GENERATE_NATIVE_HEADERS DhfsSupportNative-native
-)
-
-add_library(dhfs_support SHARED
-        src/DhfsSupportNative.cpp
-)
-
-target_compile_options(dhfs_support PRIVATE
-        -Wno-unused-parameter
-)
-
-target_link_libraries(dhfs_support PRIVATE
-        helpers
-        DhfsSupportNative-native
-)
-
-install(TARGETS dhfs_support LIBRARY DESTINATION "${DHFS_LIB_INSTALL}/${CMAKE_SYSTEM_NAME}-${CMAKE_SYSTEM_PROCESSOR}")
--- a/libdhfs_support/DhfsSupportNative/LibPathDummy.java
+++ b/libdhfs_support/DhfsSupportNative/LibPathDummy.java
@@ -1,9 +0,0 @@
-package com.usatiuk.dhfs.supportlib;
-
-import java.nio.file.Path;
-
-class DhfsNativeLibFinder {
-    static Path getLibPath() {
-        return null;
-    }
-}
--- a/libdhfs_support/DhfsSupportNative/src/DhfsSupportNative.cpp
+++ b/libdhfs_support/DhfsSupportNative/src/DhfsSupportNative.cpp
@@ -1,55 +0,0 @@
-#include <cstdio>
-#include <cstdlib>
-#include <cstdint>
-#include <cassert>
-
-#include "com_usatiuk_dhfs_supportlib_DhfsSupportNative.h"
-
-#include "Utils.h"
-#include "MemoryHelpers.h"
-
-extern "C" {
-JNIEXPORT jlong JNICALL Java_com_usatiuk_dhfs_supportlib_DhfsSupportNative_allocateUninitializedByteBuffer
-(JNIEnv* env, jclass klass, jobjectArray bb, jint size) {
-    if (size < 0) {
-        env->ThrowNew(env->FindClass("java/lang/IllegalArgumentException"), "Size less than 0?");
-        return 0;
-    }
-
-    size_t checked_size = checked_cast<size_t>(size);
-
-    void* buf;
-    if (checked_size < MemoryHelpers::get_page_size())
-        buf = malloc(checked_size);
-    else
-        buf = std::aligned_alloc(MemoryHelpers::get_page_size(),
-                                 align_up(checked_size, MemoryHelpers::get_page_size()));
-
-    if (buf == nullptr) {
-        env->ThrowNew(env->FindClass("java/lang/OutOfMemoryError"), "Buffer memory allocation failed");
-        return 0;
-    }
-
-    env->SetObjectArrayElement(bb, 0, env->NewDirectByteBuffer(buf, checked_cast<jlong>(checked_size)));
-
-    jlong token = checked_cast<jlong>((uintptr_t) buf);
-    return token;
-}
-
-JNIEXPORT void JNICALL Java_com_usatiuk_dhfs_supportlib_DhfsSupportNative_releaseByteBuffer
-(JNIEnv* env, jclass klass, jlong token) {
-    const auto addr = checked_cast<uintptr_t>(token);
-
-    if (addr == 0) {
-        env->ThrowNew(env->FindClass("java/lang/IllegalArgumentException"), "Trying to free null pointer");
-        return;
-    }
-
-    free((void*) addr);
-}
-
-JNIEXPORT jint JNICALL Java_com_usatiuk_dhfs_supportlib_DhfsSupportNative_getPageSizeInternal
-(JNIEnv*, jclass) {
-    return checked_cast<jint>(MemoryHelpers::get_page_size());
-}
-}
--- a/libdhfs_support/builder/Dockerfile
+++ b/libdhfs_support/builder/Dockerfile
@@ -1,3 +0,0 @@
-FROM rockylinux:8
-
-RUN dnf install -y java-21-openjdk-headless java-21-openjdk-devel cmake gcc gcc-c++
--- a/libdhfs_support/builder/cross-build.sh
+++ b/libdhfs_support/builder/cross-build.sh
@@ -1,56 +0,0 @@
-#!/usr/bin/env bash
-
-CMAKE_ARGS="${CMAKE_ARGS:--DCMAKE_BUILD_TYPE=Debug}"
-
-export SCRIPT_DIR=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" &>/dev/null && pwd)
-cd "$SCRIPT_DIR"
-
-if [[ "${DO_LOCAL_BUILD^^}" != "TRUE" ]]; then
-  if [[ "$(uname)" == "Linux" ]]; then
-    if [[ -z "${DOCKER_PLATFORM}" ]]; then
-      echo "Already on linux"
-      exit 0
-    fi
-  fi
-  exec "$SCRIPT_DIR"/docker-launch.sh "$@"
-fi
-
-set -euxo pipefail
-
-if [ $# -lt 3 ]; then
-  echo "Not enough arguments supplied: (build/configure) (build dir) (output dir)"
-  exit 1
-fi
-
-PROJECT_DIR="$SCRIPT_DIR/.."
-
-CONFIGURE_DIR="$2"
-INSTALL_DIR="$3"
-
-function configure() {
-  cmake -B"$CONFIGURE_DIR" -S"$PROJECT_DIR" -DDHFS_LIB_INSTALL="$INSTALL_DIR" $CMAKE_ARGS
-}
-
-function build() {
-  cmake --build "$CONFIGURE_DIR" --target install
-}
-
-mkdir -p "$2"
-mkdir -p "$3"
-
-case "$1" in
-"configure")
-  configure
-  ;;
-"build")
-  build
-  ;;
-"both")
-  configure
-  build
-  ;;
-*)
-  echo "Unknown command"
-  exit 1
-  ;;
-esac
--- a/libdhfs_support/builder/docker-launch.sh
+++ b/libdhfs_support/builder/docker-launch.sh
@@ -1,21 +0,0 @@
-#!/usr/bin/env bash
-
-set -exo pipefail
-export SCRIPT_DIR=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" &>/dev/null && pwd)
-cd "$SCRIPT_DIR"
-
-PLATFORM_ARG=""
-if [[ ! -z "${DOCKER_PLATFORM}" ]]; then
-  PLATFORM_ARG="--platform $DOCKER_PLATFORM"
-fi
-
-if [[ -z "${DOCKER_BUILDER_IMAGE}" ]]; then
-  DOCKER_IMG_FILE=$(mktemp)
-  docker build $PLATFORM_ARG --iidfile "$DOCKER_IMG_FILE" .
-  DOCKER_BUILDER_IMAGE="$(cat "$DOCKER_IMG_FILE")"
-fi
-
-ROOT_DIR="$(dirname "$(dirname "$SCRIPT_DIR")")"
-
-docker run $PLATFORM_ARG --rm -v "$ROOT_DIR:$ROOT_DIR" -e DO_LOCAL_BUILD=TRUE "$DOCKER_BUILDER_IMAGE" \
-  "$SCRIPT_DIR/cross-build.sh" "$@"
--- a/libdhfs_support/helpers/CMakeLists.txt
+++ b/libdhfs_support/helpers/CMakeLists.txt
@@ -1,9 +0,0 @@
-set(CMAKE_CXX_STANDARD 17)
-
-add_library(helpers
-        include/MemoryHelpers.h
-        src/MemoryHelpers.cpp
-        include/Utils.h
-)
-
-target_include_directories(helpers PUBLIC include)
--- a/libdhfs_support/helpers/include/MemoryHelpers.h
+++ b/libdhfs_support/helpers/include/MemoryHelpers.h
@@ -1,12 +0,0 @@
-//
-// Created by stepus53 on 24.8.24.
-//
-
-#ifndef MEMORYHELPERS_H
-#define MEMORYHELPERS_H
-
-namespace MemoryHelpers {
-unsigned int get_page_size();
-}
-
-#endif //MEMORYHELPERS_H
--- a/libdhfs_support/helpers/include/Utils.h
+++ b/libdhfs_support/helpers/include/Utils.h
@@ -1,41 +0,0 @@
-//
-// Created by stepus53 on 24.8.24.
-//
-
-#ifndef UTILS_H
-#define UTILS_H
-
-#include <cassert>
-
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wsign-conversion"
-#pragma GCC diagnostic ignored "-Wsign-compare"
-
-template<typename To, typename From>
-constexpr To checked_cast(const From& f) {
-    To result = static_cast<To>(f);
-    assert(f == result);
-    return result;
-}
-
-#pragma GCC diagnostic pop
-
-template<typename T, typename A>
-T align_up(T what, A alignment) {
-    assert(__builtin_popcount(alignment) == 1);
-
-    const T mask = checked_cast<T>(alignment - 1);
-
-    T ret;
-
-    if (what & mask)
-        ret = (what + mask) & ~mask;
-    else
-        ret = what;
-
-    assert((ret & mask) == 0);
-
-    return ret;
-}
-
-#endif //UTILS_H
--- a/libdhfs_support/helpers/src/MemoryHelpers.cpp
+++ b/libdhfs_support/helpers/src/MemoryHelpers.cpp
@@ -1,14 +0,0 @@
-//
-// Created by stepus53 on 24.8.24.
-//
-
-#include "MemoryHelpers.h"
-
-#include <unistd.h>
-
-#include "Utils.h"
-
-unsigned int MemoryHelpers::get_page_size() {
-    static const auto PAGE_SIZE = checked_cast<unsigned int>(sysconf(_SC_PAGESIZE));
-    return PAGE_SIZE;
-}
--- a/run-wrapper/run
+++ b/run-wrapper/run
@@ -36,7 +36,6 @@ java \
    -Dquarkus.http.host=0.0.0.0 \
    -Dquarkus.log.category.\"com.usatiuk\".level=INFO \
    -Dquarkus.log.category.\"com.usatiuk.dhfs\".level=INFO \
-    -Dcom.usatiuk.dhfs.supportlib.native-path="$SCRIPT_DIR"/NativeLibs \
    -Ddhfs.webui.root="$SCRIPT_DIR"/Webui $EXTRAOPTS_PARSED \
    -jar "$SCRIPT_DIR"/"DHFS Package"/quarkus-run.jar >quarkus.log 2>&1 &

--- a/thirdparty/lazyfs/build.sh
+++ b/thirdparty/lazyfs/build.sh
@@ -0,0 +1,9 @@
+# apt install g++ cmake libfuse3-dev libfuse3-3 fuse3
+
+export CMAKE_BUILD_PARALLEL_LEVEL="$(nproc)"
+
+cd lazyfs
+
+cd libs/libpcache && ./build.sh && cd -
+
+cd lazyfs && ./build.sh && cd -
--- a/thirdparty/lazyfs/lazyfs
+++ b/thirdparty/lazyfs/lazyfs
Author	SHA1	Message	Date
Stepan Usatiuk	34db870fc6	Objects: simplify TombstoneMergingKvIterator	2025-04-22 23:53:41 +02:00
Stepan Usatiuk	0e62a29ce0	Objects: cache peeked key in LmdbKvIterator	2025-04-22 23:53:18 +02:00
Stepan Usatiuk	7de5f91fd2	Dhfs-app: lazyfs crash test	2025-04-22 23:25:26 +02:00
Stepan Usatiuk	ac68208b1a	Sync-base: don't crash if invalidation queue is corrupted	2025-04-22 21:38:15 +02:00
Stepan Usatiuk	4e0675940e	Dhfs-app: better fileConflictTest	2025-04-22 21:37:51 +02:00
Stepan Usatiuk	4f5f347b3c	Use stable jnr-fuse version	2025-04-21 11:30:14 +02:00
Stepan Usatiuk	bd5395e03f	Dhfs-fs: mtime fix	2025-04-21 11:29:35 +02:00
Stepan Usatiuk	f56f564e8b	Objects: simplify TransactionManager	2025-04-21 11:15:48 +02:00
Stepan Usatiuk	eaa413e200	Objects: interfacify MaybeTombstone Data	2025-04-19 17:25:06 +02:00
Stepan Usatiuk	f3e4d99fcb	Objects: seal JDataVersionedWrapper	2025-04-19 12:07:36 +02:00
Stepan Usatiuk	1c71b26ed8	Objects: 1 less field in JDataVersionedWrapperLazy	2025-04-19 12:06:33 +02:00
Stepan Usatiuk	e6f95ef028	Remove supportlib nice idea, but ram usage explosion seems to cancel out the benefits	2025-04-19 11:32:35 +02:00
Stepan Usatiuk	59e8f6a6b4	Objects: one less copy when serializing only cache what was really read, otherwise its lifetime is the same as transaction	2025-04-19 11:03:26 +02:00
Stepan Usatiuk	0292df7f0e	Objects: faster JObjectKey	2025-04-19 11:02:30 +02:00
Stepan Usatiuk	a6a4101bb0	Objects: use bytebuffer to read a little less GC pressure	2025-04-18 13:21:04 +02:00
Stepan Usatiuk	59fa5dcf28	Fixie for HashSetDelayedBlockingQueueTest	2025-04-18 13:08:55 +02:00
Stepan Usatiuk	0f5fb8b8b6	Objects: PBT MergingIterator test	2025-04-18 13:08:40 +02:00
Stepan Usatiuk	c087dd8971	More microoptimizations 3!	2025-04-18 12:13:22 +02:00
Stepan Usatiuk	14ddddd0ff	Sync-base: use serialized certificate in self data makes it easier to switch serialization	2025-04-18 11:06:40 +02:00
Stepan Usatiuk	9859378627	Sync-base: move "_data" to suffix makes cache much less bad	2025-04-18 11:06:15 +02:00
Stepan Usatiuk	e167c21d40	More microoptimizations 2!	2025-04-17 11:48:43 +02:00
Stepan Usatiuk	7dc8f486ea	More microoptimizations!	2025-04-17 10:02:26 +02:00
Stepan Usatiuk	da1a996e6f	Support: un-simplify allocateUninitialized	2025-04-17 09:20:56 +02:00
Stepan Usatiuk	bb52a3af0e	Objects: waste less cpu in transaction commit	2025-04-17 00:26:58 +02:00
Stepan Usatiuk	de0b868349	Objects: one less sorted tree traversal in advanceIterator totally overengineering	2025-04-17 00:14:56 +02:00
Stepan Usatiuk	d4d4e150c1	Objects: use LATIN1 strings for keys should be a bit faster to match the internal string representation	2025-04-17 00:12:37 +02:00
Stepan Usatiuk	c9b0400d50	Objects: faster MergingKvIterator	2025-04-16 23:41:30 +02:00
Stepan Usatiuk	94218330b1	Simplify allocateUninitialized	2025-04-16 16:26:58 +02:00
Stepan Usatiuk	dbe2a72f7c	Objects: don't create a db_ver_obj bytebuffer every time	2025-04-16 15:39:52 +02:00