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Bloom filter not being used in MyRocks

VamsiVamsi Active Member Contributor
hi Folks,
show engine RocksDB status shows these values for bloom filter related counters:

rocksdb.bloom.filter.useful COUNT : 0

rocksdb.bloom.filter.full.positive COUNT : 192

rocksdb.bloom.filter.full.true.positive COUNT : 192

rocksdb.bloom.filter.prefix.checked COUNT : 0

rocksdb.bloom.filter.prefix.useful COUNT : 0

We have a PK that has 5 columns and we always have equality predicates on at least first 2 columns (sometimes first 4 columns as well). 

rocksdb_default_cf_options used are: write_buffer_size=256m;target_file_size_base=32m;max_bytes_for_level_base=512m;level0_file_num_compaction_trigger=4;level0_slowdown_writes_trigger=10;level0_stop_writes_trigger=15;max_write_buffer_number=4;compression_per_level=kLZ4Compression;bottommost_compression=kZSTD;compression_opts=-14:1:0;prefix_extractor=capped:12;block_based_table_factory={cache_index_and_filter_blocks=1;filter_policy=bloomfilter:10:false;whole_key_filtering=0};level_compaction_dynamic_level_bytes=true;optimize_filters_for_hits=true;compaction_pri=kMinOverlappingRatio |


What other config to set to make it use the bloom filter for PK prefix lookups? 

Thanks,

Vamsi


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