Objects: waste less cpu in transaction commit

totally overengineering

dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKey.java

@@ -26,11 +26,11 @@ 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());
+        return new JObjectKeyImpl(StandardCharsets.ISO_8859_1.decode(buff).toString());
     }
 
     @Override

dhfs-parent/objects/src/main/java/com/usatiuk/objects/JObjectKeyImpl.java

@@ -28,12 +28,12 @@ public record JObjectKeyImpl(String value) implements JObjectKey {
 
     @Override
     public byte[] bytes() {
-        return value.getBytes(StandardCharsets.UTF_8);
+        return value.getBytes(StandardCharsets.ISO_8859_1);
     }
 
     @Override
     public ByteBuffer toByteBuffer() {
-        var heapBb = StandardCharsets.UTF_8.encode(value);
+        var heapBb = StandardCharsets.ISO_8859_1.encode(value);
         if (heapBb.isDirect()) return heapBb;
         var directBb = UninitializedByteBuffer.allocateUninitialized(heapBb.remaining());
         directBb.put(heapBb);

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();
         }
     }
 

dhfs-parent/objects/src/main/java/com/usatiuk/objects/stores/LmdbObjectPersistentStore.java

@@ -2,6 +2,8 @@ package com.usatiuk.objects.stores;
 
 import com.google.protobuf.ByteString;
 import com.google.protobuf.UnsafeByteOperations;
+import com.usatiuk.dhfs.supportlib.UninitializedByteBuffer;
+import com.usatiuk.dhfs.utils.RefcountedCloseable;
 import com.usatiuk.objects.JObjectKey;
 import com.usatiuk.objects.JObjectKeyMax;
 import com.usatiuk.objects.JObjectKeyMin;
@@ -10,8 +12,6 @@ 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 +30,6 @@ 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;
 
@@ -41,10 +40,11 @@ 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 String DB_VER_OBJ_NAME_STR = "__DB_VER_OBJ";
     private static final ByteBuffer DB_VER_OBJ_NAME;
 
     static {
-        byte[] tmp = "__DB_VER_OBJ".getBytes(StandardCharsets.UTF_8);
+        byte[] tmp = DB_VER_OBJ_NAME_STR.getBytes(StandardCharsets.ISO_8859_1);
         var bb = ByteBuffer.allocateDirect(tmp.length);
         bb.put(tmp);
         bb.flip();
@@ -124,7 +124,7 @@ 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) -> !StandardCharsets.UTF_8.encode(k.value()).equals(DB_VER_OBJ_NAME.asReadOnlyBuffer()));
+                return new KeyPredicateKvIterator<>(new LmdbKvIterator(_txn.ref(), start, key), start, key, (k) -> !k.value().equals(DB_VER_OBJ_NAME_STR));
             }
 
             @Nonnull

dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/JObjectManager.java

@@ -1,11 +1,11 @@
 package com.usatiuk.objects.transaction;
 
+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;
@@ -16,7 +16,6 @@ import jakarta.inject.Inject;
 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;
 
@@ -27,6 +26,12 @@ import java.util.stream.Stream;
 @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
@@ -66,16 +71,19 @@ public class JObjectManager {
         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);
@@ -88,8 +96,9 @@ public class JObjectManager {
                 // 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);
+                    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 +109,7 @@ public class JObjectManager {
                                     }
                                 };
 
-                        var curIteration = pendingWrites.get(hook);
+                        var curIteration = hookId.pendingWrites();
 
 //                        Log.trace("Commit iteration with " + curIteration.size() + " records for hook " + hook.getClass());
 
@@ -127,12 +136,12 @@ 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++;
                             }