From acf2ae2ceff50cc8a0afd83dc2ac4d919c88e267 Mon Sep 17 00:00:00 2001
From: Stepan Usatiuk <stepan@usatiuk.com>
Date: Fri, 22 Aug 2025 23:19:39 +0200
Subject: [PATCH] less commitSnapshots created

---
 .../objects/stores/WritebackObjectPersistentStore.java   | 9 +++++++++
 .../usatiuk/objects/transaction/TransactionService.java  | 6 ++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git 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
index e5ff5302..60414dbc 100644
--- 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
@@ -307,6 +307,15 @@ public class WritebackObjectPersistentStore {
         return r -> asyncFence(bundleId, r);
     }
 
+    /**
+     * Get the last committed transaction ID.
+     *
+     * @return the last committed transaction ID
+     */
+    public long getLastCommitId() {
+        return _lastCommittedId.get();
+    }
+
     /**
      * Get a snapshot of the persistent store, including the pending writes.
      *
diff --git a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/TransactionService.java b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/TransactionService.java
index 659c6480..d1f7509d 100644
--- a/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/TransactionService.java
+++ b/dhfs-parent/objects/src/main/java/com/usatiuk/objects/transaction/TransactionService.java
@@ -165,7 +165,6 @@ public class TransactionService {
                     toUnlock.add(lock);
                 }
 
-                commitSnapshot = writebackObjectPersistentStore.getSnapshot();
             } else {
                 Log.trace("Committing transaction - no changes");
 
@@ -201,7 +200,10 @@ public class TransactionService {
             Log.trace("Committing transaction start");
             var snapshotId = tx.snapshot().id();
 
-            if (snapshotId != commitSnapshot.id()) {
+            // All dependencies are locked and could not be changed concurrently now
+            if (snapshotId != writebackObjectPersistentStore.getLastCommitId()) {
+                commitSnapshot = writebackObjectPersistentStore.getSnapshot();
+
                 for (var read : readSet.entrySet()) {
                     var current = commitSnapshot.readObject(read.getKey());