[ 
https://issues.apache.org/jira/browse/CASSANDRA-20129?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Caleb Rackliffe updated CASSANDRA-20129:
----------------------------------------
     Bug Category: Parent values: Degradation(12984)Level 1 values: Performance 
Bug/Regression(12997)
       Complexity: Normal
    Discovered By: Performance Regression Test
    Fix Version/s: 5.x
         Severity: Normal
           Status: Open  (was: Triage Needed)

> Restore optimization in MultiCBuilder around building one clustering
> --------------------------------------------------------------------
>
>                 Key: CASSANDRA-20129
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-20129
>             Project: Apache Cassandra
>          Issue Type: Bug
>          Components: Legacy/Local Write-Read Paths
>            Reporter: Caleb Rackliffe
>            Assignee: Caleb Rackliffe
>            Priority: Normal
>             Fix For: 5.x
>
>         Attachments: screenshot_2024-12-05_at_11.48.36___am_720.png, 
> screenshot_2024-12-05_at_11.49.09___am_720.png, 
> screenshot_2024-12-05_at_11.56.59___am_720.png
>
>
> Back in CASSANDRA-10409, we optimized the single clustering case for 
> {{MultiCBuilder}} to produce less garbage. In CASSANDRA-19341, we de-facto 
> removed that optimization, and I'm seeing increased allocations in trunk, 
> specifically at least double the number of {{BTree}} builders. In the 
> write-heavy workload I'm profiling, this jumps up to become the most common 
> TLAB allocation. I'm attaching JFR screenshots from 4.1 and trunk that show 
> the codepaths that touch this on both versions. We should consider 
> reintroducing something like the old {{OneClusteringBuilder}}.
> I used {{WriteBench}} to explore things here, mostly w/ the TRUNCATE 
> {{EndOp}}, and made sure commitlog writes, view updates, and 
> {{CassandraTableWriteHandler}} tracing were disabled to reduce the noise.
>  
> [~blerer]



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to