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-12107) long running apps may have a huge number of StatisticsData instances under FileSystem
Date Tue, 23 Jun 2015 04:32:01 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-12107?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14597146#comment-14597146
] 

Hadoop QA commented on HADOOP-12107:
------------------------------------

\\
\\
| (x) *{color:red}-1 overall{color}* |
\\
\\
|| Vote || Subsystem || Runtime || Comment ||
| {color:blue}0{color} | pre-patch |  16m 19s | Pre-patch trunk compilation is healthy. |
| {color:green}+1{color} | @author |   0m  0s | The patch does not contain any @author tags.
|
| {color:green}+1{color} | tests included |   0m  0s | The patch appears to include 1 new
or modified test files. |
| {color:green}+1{color} | javac |   7m 28s | There were no new javac warning messages. |
| {color:green}+1{color} | javadoc |   9m 35s | There were no new javadoc warning messages.
|
| {color:green}+1{color} | release audit |   0m 22s | The applied patch does not increase
the total number of release audit warnings. |
| {color:red}-1{color} | checkstyle |   1m  5s | The applied patch generated  1 new checkstyle
issues (total was 142, now 141). |
| {color:green}+1{color} | whitespace |   0m  1s | The patch has no lines that end in whitespace.
|
| {color:green}+1{color} | install |   1m 35s | mvn install still works. |
| {color:green}+1{color} | eclipse:eclipse |   0m 33s | The patch built with eclipse:eclipse.
|
| {color:green}+1{color} | findbugs |   1m 50s | The patch does not introduce any new Findbugs
(version 3.0.0) warnings. |
| {color:green}+1{color} | common tests |  21m 48s | Tests passed in hadoop-common. |
| | |  60m 40s | |
\\
\\
|| Subsystem || Report/Notes ||
| Patch URL | http://issues.apache.org/jira/secure/attachment/12741209/HADOOP-12107.003.patch
|
| Optional Tests | javadoc javac unit findbugs checkstyle |
| git revision | trunk / 99271b7 |
| checkstyle |  https://builds.apache.org/job/PreCommit-HADOOP-Build/7020/artifact/patchprocess/diffcheckstylehadoop-common.txt
|
| hadoop-common test log | https://builds.apache.org/job/PreCommit-HADOOP-Build/7020/artifact/patchprocess/testrun_hadoop-common.txt
|
| Test Results | https://builds.apache.org/job/PreCommit-HADOOP-Build/7020/testReport/ |
| Java | 1.7.0_55 |
| uname | Linux asf906.gq1.ygridcore.net 3.13.0-36-lowlatency #63-Ubuntu SMP PREEMPT Wed Sep
3 21:56:12 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux |
| Console output | https://builds.apache.org/job/PreCommit-HADOOP-Build/7020/console |


This message was automatically generated.

> long running apps may have a huge number of StatisticsData instances under FileSystem
> -------------------------------------------------------------------------------------
>
>                 Key: HADOOP-12107
>                 URL: https://issues.apache.org/jira/browse/HADOOP-12107
>             Project: Hadoop Common
>          Issue Type: Bug
>          Components: fs
>    Affects Versions: 2.7.0
>            Reporter: Sangjin Lee
>            Assignee: Sangjin Lee
>            Priority: Minor
>         Attachments: HADOOP-12107.001.patch, HADOOP-12107.002.patch, HADOOP-12107.003.patch
>
>
> We observed with some of our apps (non-mapreduce apps that use filesystems) that they
end up accumulating a huge memory footprint coming from {{FileSystem$Statistics$StatisticsData}}
(in the {{allData}} list of {{Statistics}}).
> Although the thread reference from {{StatisticsData}} is a weak reference, and thus can
get cleared once a thread goes away, the actual {{StatisticsData}} instances in the list won't
get cleared until any of these following methods is called on {{Statistics}}:
> - {{getBytesRead()}}
> - {{getBytesWritten()}}
> - {{getReadOps()}}
> - {{getLargeReadOps()}}
> - {{getWriteOps()}}
> - {{toString()}}
> It is quite possible to have an application that interacts with a filesystem but does
not call any of these methods on the {{Statistics}}. If such an application runs for a long
time and has a large amount of thread churn, the memory footprint will grow significantly.
> The current workaround is either to limit the thread churn or to invoke these operations
occasionally to pare down the memory. However, this is still a deficiency with {{FileSystem$Statistics}}
itself in that the memory is controlled only as a side effect of those operations.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message