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https://issues.apache.org/jira/browse/CASSANDRA-658?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12795653#action_12795653
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Stu Hood commented on CASSANDRA-658:
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Brilliant... I really like this change.
I think the main reason that we had an Atomic variable for size() in CF and SC
was to perform this calculation, so perhaps that code should be considered
dead, and removed. I noticed a bunch of subtle bugs in it last time I was
looking anyway. The size() method can remain, and calculate the size for each
call?
> Hinted Handoff CF contention
> ----------------------------
>
> Key: CASSANDRA-658
> URL: https://issues.apache.org/jira/browse/CASSANDRA-658
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Affects Versions: 0.5
> Environment: debian lenny amd64 OpenJDK 64-Bit Server VM (build
> 1.6.0_0-b11, mixed mode)
> Reporter: Brandon Williams
> Assignee: Jonathan Ellis
> Fix For: 0.9
>
> Attachments:
> 0001-use-throughput-and-op-count-instead-of-size-and-column.txt,
> 0002-replace-sharded-row-locks-with-column-level-locking.txt
>
>
> Hinted handoff causes a lot of contention on the HH CF, causing insert speed
> to massively drop. Most of the row mutation stage threads end up blocking on
> each other at Memtable.resolve. This is because HH sends the hint to the
> closest node, which will always be the node handling the write.
> To reproduce: start a cluster with even InitialTokens, and begin a constant
> stream of writes to one node, with an even key distribution. (I used 4 nodes
> and stress.py in random mode.) Take a node down, and the insert rate begin
> to drop, eventually settling between 100-300/s and sustaining there.
> Bringing the down node back up will restore the original insert rate.
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