[ 
https://issues.apache.org/jira/browse/HDFS-13594?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Lisheng Sun reassigned HDFS-13594:
----------------------------------

    Assignee: Lisheng Sun

> the lock of ShortCircuitCache is hold while close the ShortCircuitReplica  
> ---------------------------------------------------------------------------
>
>                 Key: HDFS-13594
>                 URL: https://issues.apache.org/jira/browse/HDFS-13594
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>          Components: hdfs-client
>    Affects Versions: 3.0.2
>            Reporter: Gang Xie
>            Assignee: Lisheng Sun
>            Priority: Minor
>         Attachments: no_hdfs.svg
>
>
> When we are profiling SC read, we find that ShortCircuitCache's lock is a hot 
> spot. After look into the code, we find that when close BlockReaderLocal, it 
> tries to  trimEvictionMaps, and several ShortCircuitReplicas are closed while 
> the lock being hold.  This slows down the close of the BlockReaderLocal, and 
> the worse is that it blocks the other allocating of the new 
> ShortCircuitReplicas. 
> An idea to avoid this is to close the replica in an async way. I will do a 
> prototype and get the performance.



--
This message was sent by Atlassian JIRA
(v7.6.14#76016)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org

Reply via email to