Mailing-List: contact issues-help@hbase.apache.org; run by ezmlm
Precedence: bulk
Date: Fri, 30 May 2014 14:53:02 +0000 (UTC)
From: "stack (JIRA)" <jira@apache.org>
To: issues@hbase.apache.org
Message-ID: <JIRA.12717150.1401313686851.47272.1401461582748@arcas>
In-Reply-To: <JIRA.12717150.1401313686851@arcas>
References: <JIRA.12717150.1401313686851@arcas>
Subject: [jira] [Commented] (HBASE-11267) Dynamic metrics2 metrics may
 consume large amount of heap memory
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


    [ https://issues.apache.org/jira/browse/HBASE-11267?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14013715#comment-14013715 ] 

stack commented on HBASE-11267:
-------------------------------

bq.   1:      14917882     3396492464  [C 

Is pretty opaque and how the metrics instances are being retained would be good to know.

Any testing done to first generate the reported condition so for sure this patch fixes it?

> Dynamic metrics2 metrics may consume large amount of heap memory
> ----------------------------------------------------------------
>
>                 Key: HBASE-11267
>                 URL: https://issues.apache.org/jira/browse/HBASE-11267
>             Project: HBase
>          Issue Type: Bug
>            Reporter: Ted Yu
>            Assignee: Ted Yu
>             Fix For: 0.99.0, 0.98.4
>
>         Attachments: 11267-v1.txt
>
>
> User sunweiei provided the following jmap output in 0.96 deployment:
> {code}
>  num     #instances         #bytes  class name
> ----------------------------------------------
>    1:      14917882     3396492464  [C
>    2:       1996994     2118021808  [B
>    3:      43341650     1733666000  java.util.LinkedHashMap$Entry
>    4:      14453983     1156550896  [Ljava.util.HashMap$Entry;
>    5:      14446577      924580928  org.apache.hadoop.metrics2.lib.Interns$CacheWith2Keys$2
> {code}
> Heap consumption by Interns$CacheWith2Keys$2 could be due to calls to Interns.info() in DynamicMetricsRegistry.
> This scenario would arise when large number of regions are tracked through metrics2.
> Interns class doesn't provide API to remove entries in its internal Map.
> Meaning, DynamicMetricsRegistry#clearMetrics() is unable to reclaim that part of heap.


--
This message was sent by Atlassian JIRA
(v6.2#6252)