[ https://issues.apache.org/jira/browse/CASSANDRA-15080?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Jon Haddad updated CASSANDRA-15080: ----------------------------------- Description: 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. (was: 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.) Summary: Paxos tables should use a 4KB chunk length (or no compression) (was: Paxos tables should use a 4KB chunk length) > Paxos tables should use a 4KB chunk length (or no compression) > -------------------------------------------------------------- > > Key: CASSANDRA-15080 > URL: https://issues.apache.org/jira/browse/CASSANDRA-15080 > Project: Cassandra > Issue Type: Improvement > Components: Feature/Lightweight Transactions > Reporter: 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 (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org