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ASF GitHub Bot commented on FLINK-6364: --------------------------------------- Github user StefanRRichter commented on a diff in the pull request: https://github.com/apache/flink/pull/3801#discussion_r114368960 --- Diff: flink-contrib/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/RocksDBKeyedStateBackend.java --- @@ -137,6 +156,14 @@ /** Number of bytes required to prefix the key groups. */ private final int keyGroupPrefixBytes; + /** The sst files materialized in pending checkpoints */ + private final SortedMap<Long, Map<String, StreamStateHandle>> materializedSstFiles = new TreeMap<>(); + + /** The identifier of the last completed checkpoint */ + private final long lastCompletedCheckpointId = -1; --- End diff -- Currently, this value `lastCompletedCheckpointId` is not maintained at all, and also the `materializedSstFiles` is ever-growing. I think the whole feedback from the checkpoint coordinator about completed checkpoints is still missing. Are you planning to do this in another PR? > Implement incremental checkpointing in RocksDBStateBackend > ---------------------------------------------------------- > > Key: FLINK-6364 > URL: https://issues.apache.org/jira/browse/FLINK-6364 > Project: Flink > Issue Type: Sub-task > Components: State Backends, Checkpointing > Reporter: Xiaogang Shi > Assignee: Xiaogang Shi > > {{RocksDBStateBackend}} is well suited for incremental checkpointing because > RocksDB is base on LSM trees, which record updates in new sst files and all > sst files are immutable. By only materializing those new sst files, we can > significantly improve the performance of checkpointing. -- This message was sent by Atlassian JIRA (v6.3.15#6346)