hadoop-common-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Hadoop QA (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HADOOP-9956) RPC listener inefficiently assigns connections to readers
Date Mon, 11 Nov 2013 20:09:19 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-9956?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13819313#comment-13819313
] 

Hadoop QA commented on HADOOP-9956:
-----------------------------------

{color:green}+1 overall{color}.  Here are the results of testing the latest attachment 
  http://issues.apache.org/jira/secure/attachment/12613204/HADOOP-9956.patch
  against trunk revision .

    {color:green}+1 @author{color}.  The patch does not contain any @author tags.

    {color:green}+1 tests included{color}.  The patch appears to include 1 new or modified
test files.

    {color:green}+1 javac{color}.  The applied patch does not increase the total number of
javac compiler warnings.

    {color:green}+1 javadoc{color}.  The javadoc tool did not generate any warning messages.

    {color:green}+1 eclipse:eclipse{color}.  The patch built with eclipse:eclipse.

    {color:green}+1 findbugs{color}.  The patch does not introduce any new Findbugs (version
1.3.9) warnings.

    {color:green}+1 release audit{color}.  The applied patch does not increase the total number
of release audit warnings.

    {color:green}+1 core tests{color}.  The patch passed unit tests in hadoop-common-project/hadoop-common.

    {color:green}+1 contrib tests{color}.  The patch passed contrib unit tests.

Test results: https://builds.apache.org/job/PreCommit-HADOOP-Build/3272//testReport/
Console output: https://builds.apache.org/job/PreCommit-HADOOP-Build/3272//console

This message is automatically generated.

> RPC listener inefficiently assigns connections to readers
> ---------------------------------------------------------
>
>                 Key: HADOOP-9956
>                 URL: https://issues.apache.org/jira/browse/HADOOP-9956
>             Project: Hadoop Common
>          Issue Type: Sub-task
>          Components: ipc
>    Affects Versions: 2.0.0-alpha, 3.0.0
>            Reporter: Daryn Sharp
>            Assignee: Daryn Sharp
>         Attachments: HADOOP-9956.patch, HADOOP-9956.patch
>
>
> The socket listener and readers use a complex synchronization to update the reader's
NIO {{Selector}}.  Updating active selectors is not thread-safe so precautions are required.
> However, the current locking choreography results in a serialized distribution of new
connections to the parallel socket readers.  A slower/busier reader can stall the listener
and throttle performance.
> The problem manifests as unexpectedly low cpu utilization by the listener and readers
(~20-30%) under heavy load.  The call queue is shallow when it should be overflowing.



--
This message was sent by Atlassian JIRA
(v6.1#6144)

Mime
View raw message