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https://issues.apache.org/jira/browse/HBASE-11492?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Andrew Purtell updated HBASE-11492:
-----------------------------------
Attachment: 11492.098.addendum.v2.patch
Attached updated addendum for 0.98. Set the default of
'hbase.ipc.server.tcpnodelay' to 'true' and ignore the Hadoop conf vars. We are
already doing this for the client side setting.
We shouldn't amend src/main/docbkx/ on a branch. Current release practice is to
copy src/main/* from master branch back onto the branch before generating docs.
Any changes on branch are clobbered. Left that part out.
> Hadoop configuration overrides some ipc parameters including tcpNoDelay
> -----------------------------------------------------------------------
>
> Key: HBASE-11492
> URL: https://issues.apache.org/jira/browse/HBASE-11492
> Project: HBase
> Issue Type: Bug
> Components: regionserver
> Affects Versions: 0.98.0, 0.99.0
> Reporter: Nicolas Liochon
> Assignee: Nicolas Liochon
> Priority: Critical
> Fix For: 0.99.0, 0.98.4, 2.0.0
>
> Attachments: 11492.098.addendum.patch, 11492.098.addendum.v2.patch,
> 11492.v1.patch, 11492.v1.withp1.patch, 11492.v2-0.98.patch, 11492.v2.patch,
> 11492.v2.patch, 11492.v3.patch
>
>
> There is an option to set tcpNoDelay, defaulted to true, but the socket
> channel is actually not changed. As a consequence, the server works with
> nagle enabled. This leads to very degraded behavior when a single connection
> is shared between threads. We enter into conflicts with nagle and tcp delayed
> ack.
> Here is an example of performance with the PE tool plus HBASE-11491:
> {noformat}
> oneCon #client sleep exeTime (seconds)
> avg latency, sleep excluded (microseconds)
> true 1 0 31
> 310
> false 1 0 31
> 310
> true 2 0 50
> 500
> false 2 0 31
> 310
> true 2 5 488 (including 200s sleeping)
> 2880
> false 2 5 246 (including 200s sleeping)
> 460
> {noformat}
> The latency is multiple by 5 (2880 vs 460) when the connection is shared.
> This is the delayed ack kicking in. This can be fixed by really using tcp no
> delay.
> Any application sharing the tcp connection between threads has the issue.
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