[
https://issues.apache.org/jira/browse/CASSANDRA-16078?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17263369#comment-17263369
]
Brandon Williams commented on CASSANDRA-16078:
----------------------------------------------
I've been unable to find the cause of this, my lab environment just doesn't
have enough resolution on this issue to be able to accomplish a trustworthy
bisect.
Attaching the tlp-stress class I've been using. I've done/do a few things to
make this easier to test: removed the large cumbersome bliobs, do a warmup run,
and then a run of pure reads (readrate 1) to eliminate any noise caused by
mutations/deletes for a few minutes (since with only 1k records, an hour seems
like overkill.)
[~dcapwell] could you perhaps try this class and confirm that it reproduces so
at least we'll know if I was totally off base?
> Performance regression for queries accessing multiple rows
> ----------------------------------------------------------
>
> Key: CASSANDRA-16078
> URL: https://issues.apache.org/jira/browse/CASSANDRA-16078
> Project: Cassandra
> Issue Type: Bug
> Components: Consistency/Coordination
> Reporter: David Capwell
> Assignee: Brandon Williams
> Priority: Normal
> Fix For: 4.0-beta
>
> Attachments: ClusteringSlicing.kt, image.png
>
>
> This is spin off from CASSANDRA-16036.
> In testing 4.0 relative to 3.0* I found that queries which accessed multiple
> rows to have a noticeable performance decrease; two queries were used in the
> test (more may be impacted, others might not): query partition (table has
> clustering keys) with LIMIT, and query clustering keys using IN clause.
> In the below graphs the green line is 3.0 and the other lines are 4.0 (with
> and without chunk cache)
> Partition with LIMIT
> !https://issues.apache.org/jira/secure/attachment/13009751/clustering-slice_latency_selects_baseline.png!
> !https://issues.apache.org/jira/secure/attachment/13009750/clustering-slice_latency_under90_selects_baseline.png!
> Cluster with IN clause
> !https://issues.apache.org/jira/secure/attachment/13009749/clustering-in-clause_latency_selects_baseline.png!
> !https://issues.apache.org/jira/secure/attachment/13009748/clustering-in-clause_latency_under90_selects_baseline.png!
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
