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https://issues.apache.org/jira/browse/CASSANDRA-15080?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16899160#comment-16899160
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Jeff Jirsa commented on CASSANDRA-15080:
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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.



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