[FLINK-28863][state]Add comments about why snapshot result of RocksDB…

… native savepoint doesn't have empty shared-state
mbalassi · Dec 22, 2022 · 287929c · 287929c
1 parent a56a4d3
commit 287929c
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/...a/org/apache/flink/contrib/streaming/state/snapshot/RocksIncrementalSnapshotStrategy.java b/...a/org/apache/flink/contrib/streaming/state/snapshot/RocksIncrementalSnapshotStrategy.java
@@ -294,6 +294,15 @@ public SnapshotResult<KeyedStateHandle> get(CloseableRegistry snapshotCloseableR
  checkpointedSize += getUploadedStateSize(sstFiles.values());
  checkpointedSize += getUploadedStateSize(miscFiles.values());
 
+ // We make the 'sstFiles' as the 'sharedState' in IncrementalRemoteKeyedStateHandle,
+ // whether they belong to the sharded CheckpointedStateScope or exclusive
+ // CheckpointedStateScope.
+ // In this way, the first checkpoint after job recovery can be an incremental
+ // checkpoint in CLAIM mode, either restoring from checkpoint or restoring from
+ // native savepoint.
+ // And this has no effect on the registration of shareState currently, because the
+ // snapshot result of native savepoint would not be registered into
+ // 'SharedStateRegistry'.
  final IncrementalRemoteKeyedStateHandle jmIncrementalKeyedStateHandle =
  new IncrementalRemoteKeyedStateHandle(
  backendUID,