[
https://issues.apache.org/jira/browse/MAPREDUCE-6436?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14630890#comment-14630890
]
Hadoop QA commented on MAPREDUCE-6436:
--------------------------------------
\\
\\
| (x) *{color:red}-1 overall{color}* |
\\
\\
|| Vote || Subsystem || Runtime || Comment ||
| {color:blue}0{color} | pre-patch | 16m 18s | Pre-patch trunk compilation is
healthy. |
| {color:green}+1{color} | @author | 0m 0s | The patch does not contain any
@author tags. |
| {color:red}-1{color} | tests included | 0m 0s | The patch doesn't appear
to include any new or modified tests. Please justify why no new tests are
needed for this patch. Also please list what manual steps were performed to
verify this patch. |
| {color:green}+1{color} | javac | 8m 4s | There were no new javac warning
messages. |
| {color:green}+1{color} | javadoc | 10m 12s | 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 | 0m 30s | The applied patch generated 1
new checkstyle issues (total was 16, now 17). |
| {color:red}-1{color} | whitespace | 0m 0s | The patch has 1 line(s) that
end in whitespace. Use git apply --whitespace=fix. |
| {color:green}+1{color} | install | 1m 25s | mvn install still works. |
| {color:green}+1{color} | eclipse:eclipse | 0m 33s | The patch built with
eclipse:eclipse. |
| {color:green}+1{color} | findbugs | 0m 53s | The patch does not introduce
any new Findbugs (version 3.0.0) warnings. |
| {color:green}+1{color} | mapreduce tests | 5m 53s | Tests passed in
hadoop-mapreduce-client-hs. |
| | | 44m 15s | |
\\
\\
|| Subsystem || Report/Notes ||
| Patch URL |
http://issues.apache.org/jira/secure/attachment/12745774/MAPREDUCE-6436.1.patch
|
| Optional Tests | javadoc javac unit findbugs checkstyle |
| git revision | trunk / ee36f4f |
| checkstyle |
https://builds.apache.org/job/PreCommit-MAPREDUCE-Build/5894/artifact/patchprocess/diffcheckstylehadoop-mapreduce-client-hs.txt
|
| whitespace |
https://builds.apache.org/job/PreCommit-MAPREDUCE-Build/5894/artifact/patchprocess/whitespace.txt
|
| hadoop-mapreduce-client-hs test log |
https://builds.apache.org/job/PreCommit-MAPREDUCE-Build/5894/artifact/patchprocess/testrun_hadoop-mapreduce-client-hs.txt
|
| Test Results |
https://builds.apache.org/job/PreCommit-MAPREDUCE-Build/5894/testReport/ |
| Java | 1.7.0_55 |
| uname | Linux asf904.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-MAPREDUCE-Build/5894/console |
This message was automatically generated.
> JobHistory cache issue
> ----------------------
>
> Key: MAPREDUCE-6436
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-6436
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Reporter: Ryu Kobayashi
> Assignee: Ryu Kobayashi
> Attachments: MAPREDUCE-6436.1.patch, stacktrace1.txt,
> stacktrace2.txt, stacktrace3.txt
>
>
> Problem:
> HistoryFileManager.addIfAbsent produces large amount of logs if number of
> cached entries whose age is less than mapreduce.jobhistory.max-age-ms becomes
> larger than mapreduce.jobhistory.joblist.cache.size by far.
> Example:
> For example, if the cache contains 50000 entries in total and 10,000 entries
> newer than mapreduce.jobhistory.max-age-ms where
> mapreduce.jobhistory.joblist.cache.size is 20000,
> HistoryFileManager.addIfAbsent
> method produces 50000 - 20000 = 30000 lines of "Waiting to remove <key> from
> JobListCache because it is not in done yet" message.
> It will attach a stacktrace.
> Impact:
> In addition to large disk consumption, this issue blocks JobHistory.getJob
> long time and slows job execution down significantly because getJob is called
> by RPC such as HistoryClientService.HSClientProtocolHandler.getJobReport.
> This impact happens because HistoryFileManager.UserLogDir.scanIfNeeded
> eventually calls HistoryFileManager.addIfAbsent in a synchronized block. When
> multiple threads call scanIfNeeded simultaneously, one of them acquires lock
> and the other threads are blocked until the first thread completes
> long-running
> HistoryFileManager.addIfAbsent call.
> Solution:
> * Reduce amount of logs so that HistoryFileManager.addIfAbsent doesn't take
> too long time.
> * Good to have if possible: HistoryFileManager.UserLogDir.scanIfNeeded skips
> scanning if another thread is already scanning. This changes semantics of
> some HistoryFileManager methods (such as getAllFileInfo and getFileInfo)
> because scanIfNeeded keep outdated state.
> * Good to have if possible: Make scanIfNeeded asynchronous so that RPC calls
> are
> not blocked by a loop at scale of tens of thousands.
>
> This patch implemented the first item.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
