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https://issues.apache.org/jira/browse/CASSANDRA-18766?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17873298#comment-17873298
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Brandon Williams edited comment on CASSANDRA-18766 at 8/13/24 9:45 PM:
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I was hoping this would provide a smoking gun that I could use to bisect and 
finally find the culprit, so I converted this to a dtest 
[here|https://github.com/driftx/cassandra-dtest/commit/68cb71920c9242aeb0e0cc3eb7e998175d9b5ccb].
  Unfortunately however, this doesn't reproduce for me, on any of 4.0, 4.1, or 
5.0 when run on isolated hardware.  I also checked the raw SR numbers from each 
and they are comparable across the branches.

-[~aswinkarthik] was this run on isolated hardware and does this consistently 
reproduce for you?-

edit: I modified the test to check SR on all the nodes, and now I'm seeing 
failures.


was (Author: brandon.williams):
I was hoping this would provide a smoking gun that I could use to bisect and 
finally find the culprit, so I converted this to a dtest 
[here|https://github.com/driftx/cassandra-dtest/commit/68cb71920c9242aeb0e0cc3eb7e998175d9b5ccb].
  Unfortunately however, this doesn't reproduce for me, on any of 4.0, 4.1, or 
5.0 when run on isolated hardware.  I also checked the raw SR numbers from each 
and they are comparable across the branches.

[~aswinkarthik] was this run on isolated hardware and does this consistently 
reproduce for you?

> high speculative retries on v4.1.3
> ----------------------------------
>
>                 Key: CASSANDRA-18766
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-18766
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Consistency/Coordination
>            Reporter: Ivans Novikovs
>            Assignee: Brandon Williams
>            Priority: Urgent
>             Fix For: 4.1.x
>
>         Attachments: screenshot-1.png, screenshot-2.png, signature.asc, 
> signature.asc, v4.0.png, v4.1.png
>
>
> There are up to 10+ times higher speculative retries for reads on 4.1.3 
> comparing to 4.0.7 and 4.1.2 when using QUORUM and default setting of 99p.
> On 4.1.3 after upgrade I see speculative retries for up to 35% of all reads 
> for specific table. Latency for reads is stable around 500 microseconds.
> java 1.8.0_382 is used



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