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Jeff Jirsa commented on CASSANDRA-15080: ---------------------------------------- Mentioned this in slack, but I think hard coding this is probably wrong. There are some real and valid use cases where payloads are much larger than 4k, so those would see a meaningful regression here. There may be a middle ground, or it may make sense to be somewhat configurable. > Paxos tables should use a 4KB chunk length > ------------------------------------------ > > Key: CASSANDRA-15080 > URL: https://issues.apache.org/jira/browse/CASSANDRA-15080 > Project: Cassandra > Issue Type: Improvement > Components: Feature/Lightweight Transactions > Reporter: Jon Haddad > Assignee: Jon Haddad > Priority: Normal > Labels: performance > Attachments: flamegraph-bad-perf.svg > > > In doing some research for a client on LWTs, I found that once we start > pushing a node hard enough, with enough LWTs, decompressing the data in the > paxos table takes up quite a bit of time. I've attached an SVG flame graph > showing about 10% of time is spent in LZ4_decompress_fast in queries hitting > the paxos table. We should be able to get a nice little performance bump > from changing this to 4KB chunk length or disabling it completely. -- This message was sent by Atlassian JIRA (v7.6.14#76016) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org