hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Hudson (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-8597) compaction record (probably) can block WAL cleanup forever if region is closed without edits
Date Sat, 25 May 2013 00:55:26 GMT

    [ https://issues.apache.org/jira/browse/HBASE-8597?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13666877#comment-13666877
] 

Hudson commented on HBASE-8597:
-------------------------------

Integrated in HBase-TRUNK #4142 (See [https://builds.apache.org/job/HBase-TRUNK/4142/])
    HBASE-8597 compaction record (probably) can block WAL cleanup forever if region is closed
without edits (Sergey) (Revision 1486212)

     Result = SUCCESS
tedyu : 
Files : 
* /hbase/trunk/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/FSHLog.java
* /hbase/trunk/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/HLog.java
* /hbase/trunk/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/HLogUtil.java
* /hbase/trunk/hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseTestingUtility.java
* /hbase/trunk/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestLogRolling.java

                
> compaction record (probably) can block WAL cleanup forever if region is closed without
edits
> --------------------------------------------------------------------------------------------
>
>                 Key: HBASE-8597
>                 URL: https://issues.apache.org/jira/browse/HBASE-8597
>             Project: HBase
>          Issue Type: Bug
>    Affects Versions: 0.95.0
>            Reporter: Sergey Shelukhin
>            Assignee: Sergey Shelukhin
>            Priority: Blocker
>             Fix For: 0.98.0, 0.95.1
>
>         Attachments: 8597-v2.patch, HBASE-8597-v0.patch, HBASE-8597-v1.patch
>
>
> A region is opened by a server, major compaction is performed, that triggers a split,
and the region is closed and split. There's no indication of memstore flush for this region.
> After that, LogRoller repeatedly tries to request the flush of this region due to large
number of HLogs, but fails to flush it for hours because the region is not in online regions.
> It seems that what's happening is that when we append entries to WAL we add the first
entry after we flush/open some region to "earliest unflushed seqNums per region" map in FSHLog.
However, compaction now adds compaction record to WAL, which also affects this map. If the
compaction record is the first entry for this region to go into some WAL, and there are no
writes to the region after that, there will be no memstore flush and the entry will never
be removed. 
> In fact "flushing" for compaction record doesn't make sense, there's no  preservation
of the record outside WAL; so, we probably should not add it to "latest unflushed" map.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message