[FLINK-32833] Rocksdb CacheIndexAndFilterBlocks must be true when using shared memory

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.17.1
• Component/s: Runtime / State Backends
• Assignee: Unassigned
• Reporter: Yue Ma
• Created: 11/Aug/23 07:35
• Updated: 14/Aug/23 06:03

Description

Currently in RocksDBResourceContainer#getColumnOptions, if sharedResources is used, blockBasedTableConfig will add the following configuration by default.

blockBasedTableConfig.setBlockCache(blockCache);
blockBasedTableConfig.setCacheIndexAndFilterBlocks(true);
blockBasedTableConfig.setCacheIndexAndFilterBlocksWithHighPriority(true);
blockBasedTableConfig.setPinL0FilterAndIndexBlocksInCache(true);

In my understanding, these configurations can help flink better manage the memory of rocksdb and save some memory overhead in some scenarios. But this may not be the best practice, mainly for the following reasons:
1. After CacheIndexAndFilterBlocks is set to true, it may cause index and filter miss when reading, resulting in performance degradation.
2. These parameters may not be bound together with whether shared memory is used, or some configurations should be supported separately to decide whether to enable these features

Issue Links

• relates to: FLINK-7289 Memory allocation of RocksDB can be problematic in container environments