hadoop-common-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Hudson (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HADOOP-9956) RPC listener inefficiently assigns connections to readers
Date Thu, 14 Nov 2013 13:43:25 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-9956?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13822430#comment-13822430
] 

Hudson commented on HADOOP-9956:
--------------------------------

SUCCESS: Integrated in Hadoop-Hdfs-trunk #1582 (See [https://builds.apache.org/job/Hadoop-Hdfs-trunk/1582/])
Move HADOOP-9956 to correct release in CHANGES.txt (daryn: http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1541740)
* /hadoop/common/trunk/hadoop-common-project/hadoop-common/CHANGES.txt
HADOOP-9956. RPC listener inefficiently assigns connections to readers (daryn) (daryn: http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1541736)
* /hadoop/common/trunk/hadoop-common-project/hadoop-common/CHANGES.txt
* /hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/CommonConfigurationKeys.java
* /hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/Server.java
* /hadoop/common/trunk/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/ipc/TestIPC.java


> 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
>             Fix For: 3.0.0, 2.3.0, 0.23.10
>
>         Attachments: HADOOP-9956.branch-23.patch, 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