[FLINK-30461] Some rocksdb sst files will remain forever - ASF JIRA

XML

Word

Printable

JSON

Details

Type: Bug
Status: Resolved
Priority: Major
Resolution: Fixed
Affects Version/s: 1.16.0, 1.17.0, 1.15.3
Fix Version/s: 1.17.0, 1.15.4, 1.16.2
Component/s: Runtime / Checkpointing, Runtime / State Backends
Labels:
- pull-request-available

Release Note:
clean-up left-over rocksdb ssts in the shared scope introduced in ~~FLINK-11008~~ (Flink version 1.8)

Description

In rocksdb incremental checkpoint mode, during file upload, if some files have been uploaded and some files have not been uploaded, the checkpoint is canceled due to checkpoint timeout at this time, and the uploaded files will remain.

Impact:

The shared directory of a flink job has more than 1 million files. It exceeded the hdfs upper limit, causing new files not to be written.

However only 50k files are available, the other 950k files should be cleaned up.

Root cause:

If an exception is thrown during the checkpoint async phase, flink will clean up metaStateHandle, miscFiles and sstFiles.

However, when all sst files are uploaded, they are added together to sstFiles. If some sst files have been uploaded and some sst files are still being uploaded, and the checkpoint is canceled due to checkpoint timeout at this time, all sst files will not be added to sstFiles. The uploaded sst will remain on hdfs.

code link

Solution:

Using the CloseableRegistry as the tmpResourcesRegistry. If the async phase is failed, the tmpResourcesRegistry will cleanup these temporary resources.

POC code:

https://github.com/1996fanrui/flink/commit/86a456b2bbdad6c032bf8e0bff71c4824abb3ce1