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Ryan King commented on CASSANDRA-1555: -------------------------------------- Yeah, you're right, we need to upgrade to the 64bit version. Our options with backward-compat seem to be: 1) keep 2 separete BF impl's- each with their own bitset and hash function 2) regenerate the BF the first time we start up with this patch I'd lean towards #2, but am open to other suggestions. > 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 > Assignee: Ryan King > Fix For: 0.8 > > Attachments: cassandra-1555.tgz > > > To (optimally) support SSTables larger than 143 million keys, we need to > support bloom filters larger than 2^31 bits, which java.util.BitSet can't > handle directly. > A few options: > * Switch to a BitSet class which supports 2^31 * 64 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.