Hi This difference of data size of incremental vs full checkpoint is due to the different implementations. The incremental checkpoint strategy upload binary sst files while full checkpoint strategy scans the DB and write all kv entries to external DFS.
As your state size is really small (only 200 KB), I think your RocksDB has not ever triggered compaction to reduce sst files, that's why the size constantly increase. Best Yun Tang ________________________________ From: sudranga <sud.r...@gmail.com> Sent: Wednesday, October 14, 2020 10:40 To: user@flink.apache.org <user@flink.apache.org> Subject: Rocksdb - Incremental vs full checkpoints Hi, I have an event-window pipeline which handles a fixed number of messages per second for a fixed number of keys. When i have rocksdb as the state backend with incremental checkpoints, i see the delta checkpoint size constantly increase. Please see <http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/file/t2790/Screen_Shot_2020-10-13_at_6.png> I turned off incremental checkpoints and all the checkpoints are 64kb (There appears to be no state leak in user code or otherwise). It is not clear why the incremental checkpoints keep increasing in size. Perhaps, the incremental checkpoints are not incremental(for this small state size) and are simply full state appended to full state and so on... >From some posts on this forum, I understand the use case for incremental checkpoints is designed when the state size is fairly large (Gbs-Tbs) and where the changes in state are minimal across checkpoints. However, does this mean that we should not enable incremental checkpointing for use cases where the state size is much smaller? Would the 'constantly' increasing snapshot delta size reduce at some point? I don't see any compaction runs happening (taskmanager_job_task_operator_column_family_rocksdb.num-running-compactions). Not sure if that is what I am missing... Thanks Sudharsan -- Sent from: http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/
