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Pavel Yaskevich commented on CASSANDRA-3772: -------------------------------------------- My tests show that Murmur3Partitioner actually is worse than MD5 with high cardinality indexes, here is what I did (kernel 3.0.0-19, 2.2Ghz quad-core Opteron, 2GB RAM): For each test: - wiped all of the data directories and re-compiled with 'clean' - ran stress with -c 50 -C 500 -S 512 -n 50000 (where -c is number of columns, -C values cardinality and -S is value size in bytes) 4 times (to make it hot) RandomPartitioner: average op rate is 845. Murmur3Partitioner: average op rage is 721. > Evaluate Murmur3-based partitioner > ---------------------------------- > > Key: CASSANDRA-3772 > URL: https://issues.apache.org/jira/browse/CASSANDRA-3772 > Project: Cassandra > Issue Type: New Feature > Components: Core > Reporter: Jonathan Ellis > Assignee: Pavel Yaskevich > Fix For: 1.3 > > Attachments: 0001-CASSANDRA-3772.patch, > 0001-CASSANDRA-3772-Test.patch, hashed_partitioner_3.diff, > hashed_partitioner.diff, MumPartitionerTest.docx, try_murmur3_2.diff, > try_murmur3.diff > > > MD5 is a relatively heavyweight hash to use when we don't need cryptographic > qualities, just a good output distribution. Let's see how much overhead we > can save by using Murmur3 instead. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira