2 Commits (894c6d21aff74d1edd2a355f52f2315d5ba58a60)

Author	SHA1	Message	Date
Levi Tamasi	d92a59b6f2	Fix regression affecting partitioned indexes/filters when cache_index_and_filter_blocks is false (#5705) ... Summary: PR https://github.com/facebook/rocksdb/issues/5298 (and subsequent related patches) unintentionally changed the semantics of cache_index_and_filter_blocks: historically, this option only affected the main index/filter block; with the changes, it affects index/filter partitions as well. This can cause performance issues when cache_index_and_filter_blocks is false since in this case, partitions are neither cached nor preloaded (i.e. they are loaded on demand upon each access). The patch reverts to the earlier behavior, that is, partitions are cached similarly to data blocks regardless of the value of the above option. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5705 Test Plan: make check ./db_bench -benchmarks=fillrandom --statistics --stats_interval_seconds=1 --duration=30 --num=500000000 --bloom_bits=20 --partition_index_and_filters=true --cache_index_and_filter_blocks=false ./db_bench -benchmarks=readrandom --use_existing_db --statistics --stats_interval_seconds=1 --duration=10 --num=500000000 --bloom_bits=20 --partition_index_and_filters=true --cache_index_and_filter_blocks=false --cache_size=8000000000 Relevant statistics from the readrandom benchmark with the old code: rocksdb.block.cache.index.miss COUNT : 0 rocksdb.block.cache.index.hit COUNT : 0 rocksdb.block.cache.index.add COUNT : 0 rocksdb.block.cache.index.bytes.insert COUNT : 0 rocksdb.block.cache.index.bytes.evict COUNT : 0 rocksdb.block.cache.filter.miss COUNT : 0 rocksdb.block.cache.filter.hit COUNT : 0 rocksdb.block.cache.filter.add COUNT : 0 rocksdb.block.cache.filter.bytes.insert COUNT : 0 rocksdb.block.cache.filter.bytes.evict COUNT : 0 With the new code: rocksdb.block.cache.index.miss COUNT : 2500 rocksdb.block.cache.index.hit COUNT : 42696 rocksdb.block.cache.index.add COUNT : 2500 rocksdb.block.cache.index.bytes.insert COUNT : 4050048 rocksdb.block.cache.index.bytes.evict COUNT : 0 rocksdb.block.cache.filter.miss COUNT : 2500 rocksdb.block.cache.filter.hit COUNT : 4550493 rocksdb.block.cache.filter.add COUNT : 2500 rocksdb.block.cache.filter.bytes.insert COUNT : 10331040 rocksdb.block.cache.filter.bytes.evict COUNT : 0 Differential Revision: D16817382 Pulled By: ltamasi fbshipit-source-id: 28a516b0da1f041a03313e0b70b28cf5cf205d00	5 years ago
Levi Tamasi	3bde41b5a3	Move the filter readers out of the block cache (#5504) ... Summary: Currently, when the block cache is used for the filter block, it is not really the block itself that is stored in the cache but a FilterBlockReader object. Since this object is not pure data (it has, for instance, pointers that might dangle, including in one case a back pointer to the TableReader), it's not really sharable. To avoid the issues around this, the current code erases the cache entries when the TableReader is closed (which, BTW, is not sufficient since a concurrent TableReader might have picked up the object in the meantime). Instead of doing this, the patch moves the FilterBlockReader out of the cache altogether, and decouples the filter reader object from the filter block. In particular, instead of the TableReader owning, or caching/pinning the FilterBlockReader (based on the customer's settings), with the change the TableReader unconditionally owns the FilterBlockReader, which in turn owns/caches/pins the filter block. This change also enables us to reuse the code paths historically used for data blocks for filters as well. Note: Eviction statistics for filter blocks are temporarily broken. We plan to fix this in a separate phase. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5504 Test Plan: make asan_check Differential Revision: D16036974 Pulled By: ltamasi fbshipit-source-id: 770f543c5fb4ed126fd1e04bfd3809cf4ff9c091	5 years ago