What is your bloom_filter_fp_chance for either table? I guess it is bigger for the first one, bigger that number is between 0 and 1, less memory it will use (17 MiB against 54.9 Mib) which means more false positives you will get.
On Wed, 17 Apr 2019 at 19:59, Martin Mačura <m.mac...@gmail.com> wrote: > > Hi, > I have a table with poor bloom filter false ratio: > SSTable count: 1223 > Space used (live): 726.58 GiB > Number of partitions (estimate): 8592749 > Bloom filter false positives: 35796352 > Bloom filter false ratio: 0.68472 > Bloom filter space used: 17.82 MiB > Compacted partition maximum bytes: 386857368 > > It's a time series, TWCS compaction, window size 1 day, data partitioned in > daily buckets, TTL 2 years. > > I have another table with a similar schema, but it is not affected for some > reason: > SSTable count: 1114 > Space used (live): 329.87 GiB > Number of partitions (estimate): 25460768 > Bloom filter false positives: 156942 > Bloom filter false ratio: 0.00010 > Bloom filter space used: 54.9 MiB > Compacted partition maximum bytes: 20924300 > > Thanks for any advice, > > Martin --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org For additional commands, e-mail: user-h...@cassandra.apache.org
