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Sylvain Lebresne commented on CASSANDRA-1555: --------------------------------------------- Even if we should probably have a way to support big BF, it would still be nice to be able to configure the BF FP rate. 2+GB for BFs can start to be an heavy weight on your memory. For some loads, it could be better to actually keep your memory for row cache for instance. > Considerations for larger bloom filters > --------------------------------------- > > Key: CASSANDRA-1555 > URL: https://issues.apache.org/jira/browse/CASSANDRA-1555 > Project: Cassandra > Issue Type: Improvement > Components: Core > Reporter: Stu Hood > Fix For: 0.8 > > > To (optimally) support SSTables larger than 143 million keys, we need to > support bloom filters larger than 2 GB, which java.util.BitSet can't handle > directly. > A few options: > * Switch to a BitSet class which supports 2^63 bits (Lucene's OpenBitSet) > * Partition the java.util.BitSet behind our current BloomFilter > ** Straightforward bit partitioning: bit N is in bitset N // 2^31 > ** Separate equally sized complete bloom filters for member ranges, which can > be used independently or OR'd together under memory pressure. > All of these options require new approaches to serialization. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.