Delete snapshot chunks while truncating log entries

MicroRaft · Mar 24, 2024 · 25fc07b · 25fc07b
1 parent 04b620f
commit 25fc07b
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Showing 5 changed files with 21 additions and 11 deletions.
diff --git a/microraft-store-sqlite/src/main/java/io/microraft/store/sqlite/RaftSqliteStore.java b/microraft-store-sqlite/src/main/java/io/microraft/store/sqlite/RaftSqliteStore.java
@@ -200,6 +200,8 @@ public void truncateLogEntriesFrom(@Nonnegative long logIndexInclusive) {
     @Override
     public void truncateLogEntriesUntil(@Nonnegative long logIndexInclusive) {
         dsl.deleteFrom(LOG_ENTRIES).where(INDEX.lessOrEqual(logIndexInclusive)).execute();
+        // we can remove all snapshot chunks belonging to the previous log indices
+        dsl.deleteFrom(SNAPSHOT_CHUNKS).where(INDEX.lessThan(logIndexInclusive)).execute();
     }
 
     /**

diff --git a/microraft-store-sqlite/src/test/java/io/microraft/store/sqlite/RaftSqliteStoreTest.java b/microraft-store-sqlite/src/test/java/io/microraft/store/sqlite/RaftSqliteStoreTest.java
@@ -114,18 +114,25 @@ public void testLogEntryFlushing() {
     public void testSnapshots() throws IOException {
         withRaftStore(RaftSqliteStoreTest::persistInitialState);
         withRaftStore(store -> {
-            store.persistLogEntries(List.of(logEntry(1, 1), logEntry(2, 1), logEntry(3, 1)));
+            store.persistLogEntries(List.of(logEntry(1, 1), logEntry(2, 1), logEntry(3, 1), logEntry(4, 1)));
             store.flush();
-            store.persistSnapshotChunk(snapshotChunk(2, 0, 0, 1));
+            store.persistSnapshotChunk(snapshotChunk(2, 1, 0, 1));
             store.flush();
             // once a snapshot chunk has been flushed, irrelevant log entries can be deleted
             store.truncateLogEntriesUntil(2);
             store.flush();
+            store.persistSnapshotChunk(snapshotChunk(3, 1, 0, 1));
+            store.flush();
+            // once a snapshot chunk has been flushed, irrelevant log entries can be deleted
+            store.truncateLogEntriesUntil(3);
+            store.flush();
+            assertThat(store.getAllSnapshotChunks()).usingRecursiveFieldByFieldElementComparator()
+                    .containsExactly(snapshotChunk(3, 1, 0, 1));
             RestoredRaftState restoredRaftState = store.getRestoredRaftState(false).get();
             assertThat(restoredRaftState.getLogEntries()).usingRecursiveFieldByFieldElementComparator()
-                    .containsExactly(logEntry(3, 1));
+                    .containsExactly(logEntry(4, 1));
             assertThat(restoredRaftState.getSnapshotEntry().getOperation()).usingRecursiveComparison()
-                    .isEqualTo(List.of(snapshotChunk(2, 0, 0, 1)));
+                    .isEqualTo(List.of(snapshotChunk(3, 1, 0, 1)));
         });
         sqlite = new File(tempDir.newFolder(), "sqlite.db");
         withRaftStore(RaftSqliteStoreTest::persistInitialState);

diff --git a/microraft/src/main/java/io/microraft/impl/state/RaftGroupMembersState.java b/microraft/src/main/java/io/microraft/impl/state/RaftGroupMembersState.java
@@ -147,8 +147,8 @@ public boolean isKnownMember(RaftEndpoint endpoint) {
     }
 
     /**
-     * Returns true if the given endpoint is a voting member of the Raft group, false
-     * otherwise.
+     * Returns true if the given endpoint is a voting member of the Raft group,
+     * false otherwise.
      */
     public boolean isVotingMember(RaftEndpoint endpoint) {
         return votingMembers.contains(endpoint);

diff --git a/microraft/src/main/java/io/microraft/impl/state/RaftState.java b/microraft/src/main/java/io/microraft/impl/state/RaftState.java
@@ -596,8 +596,8 @@ public boolean isKnownMember(RaftEndpoint endpoint) {
     }
 
     /**
-     * Returns true if the given endpoint is a voting member in the effective group members, false
-     * otherwise.
+     * Returns true if the given endpoint is a voting member in the effective group
+     * members, false otherwise.
      */
     public boolean isVotingMember(RaftEndpoint endpoint) {
         return effectiveGroupMembers.isVotingMember(endpoint);

diff --git a/microraft/src/main/java/io/microraft/persistence/RaftStore.java b/microraft/src/main/java/io/microraft/persistence/RaftStore.java
@@ -194,14 +194,15 @@ void persistAndFlushLocalEndpoint(@Nonnull RaftEndpointPersistentState localEndp
 
     /**
      * MicroRaft calls this method after it successfully persists and flushes a
-     * snapshot. This method is used for deleting log entries that are before the
-     * snapshot index and are not needed to be restored.
+     * snapshot. This method is used for deleting log entries and snapshot chunks
+     * that are before the snapshot index and are not needed to be restored.
      *
      * This is merely an optimization method and its side-effects can be sync'ed to
      * the storage when {@link #flush()} is called,
      *
      * @param logIndexInclusive
-     *            the log index value until which the log entries must be truncated
+     *            the log index value until which the log entries and snapshot
+     *            chunks must be truncated
      *
      * @throws IOException
      *             if any failure occurs during truncating the log entries