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https://issues.apache.org/jira/browse/CASSANDRA-15080?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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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 allow the user to modify the compression settings on this table.

  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 or disabling it completely.


> Paxos tables should allow a configurable 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 allow the user to modify the compression settings on this table.



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