[jira] [Updated] (HDFS-11907) NameNodeResourceChecker should avoid calling df.getAvailable too frequently

["Chen Liang (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/HDFS-11907?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Chen Liang updated HDFS-11907:
------------------------------
    Attachment: HDFS-11907.003.patch

Thanks [~arpitagarwal] for the comments! all addressed in v003 patch.

> NameNodeResourceChecker should avoid calling df.getAvailable too frequently
> ---------------------------------------------------------------------------
>
>                 Key: HDFS-11907
>                 URL: https://issues.apache.org/jira/browse/HDFS-11907
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>            Reporter: Chen Liang
>            Assignee: Chen Liang
>         Attachments: HDFS-11907.001.patch, HDFS-11907.002.patch, HDFS-11907.003.patch
>
>
> Currently, {{HealthMonitor#doHealthChecks}} invokes {{NameNode#monitorHealth}} which ends up invoking {{NameNodeResourceChecker#isResourceAvailable}}, at the frequency of once per second by default. And NameNodeResourceChecker#isResourceAvailable invokes {{df.getAvailable();}} every time it is called.
> Since available space information should rarely be changing dramatically at the pace of per second. A cached value should be sufficient. i.e. only try to get the updated value when the cached value is too old. otherwise simply return the cached value. This way df.getAvailable() gets invoked less.
> Thanks [~arpitagarwal] for the offline discussion.



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)

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