hbase-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "stack (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HBASE-674) memcache size unreliable
Date Mon, 09 Jun 2008 21:30:45 GMT

    [ https://issues.apache.org/jira/browse/HBASE-674?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12603695#action_12603695

stack commented on HBASE-674:

Issue is a regionserver that is stuck with the block gate down.  I can see it flushing over
time but the memcache size continues to crawl until its at maximum and then never goes down
in spite of fact we've been regularly flushing.  Our math is obviously off... See here:

2008-06-05 23:29:54,872 DEBUG org.apache.hadoop.hbase.HRegion: Started memcache flush for
region enwiki_meta,4xm9tOa_JLlpDI7EFNz4OF==,1212282770124. Current region memcache size 10.7m
2008-06-05 23:29:56,246 DEBUG org.apache.hadoop.hbase.HStore: Added /hbase/aa0-005-2.u.powerset.com/enwiki_meta/1966274647/alternate_title/mapfiles/7141575363599707225
with 4 entries, sequence id 1109246475, data size 290.0
2008-06-05 23:29:56,444 DEBUG org.apache.hadoop.hbase.HStore: Added /hbase/aa0-005-2.u.powerset.com/enwiki_meta/1966274647/misc/mapfiles/8160270909949078904
with 39 entries, sequence id 1109246475, data size 2.3k
2008-06-05 23:29:56,661 DEBUG org.apache.hadoop.hbase.HStore: Added /hbase/aa0-005-2.u.powerset.com/enwiki_meta/1966274647/alternate_url/mapfiles/3974349317844214611
with 4 entries, sequence id 1109246475, data size 398.0
2008-06-05 23:29:56,889 DEBUG org.apache.hadoop.hbase.HStore: Added /hbase/aa0-005-2.u.powerset.com/enwiki_meta/1966274647/page/mapfiles/5684117091377129929
with 117 entries, sequence id 1109246475, data size 87.0k
2008-06-05 23:29:56,890 DEBUG org.apache.hadoop.hbase.HRegion: Finished memcache flush for
region enwiki_meta,4xm9tOa_JLlpDI7EFNz4OF==,1212282770124 in 2019ms, sequence id=1109246475

See how we are at 10.7M when flush starts but how if you count up all that was flushed, we
flushed 90k odd.

> memcache size unreliable
> ------------------------
>                 Key: HBASE-674
>                 URL: https://issues.apache.org/jira/browse/HBASE-674
>             Project: Hadoop HBase
>          Issue Type: Bug
>    Affects Versions: 0.1.2
>            Reporter: stack
>            Priority: Blocker
>             Fix For: 0.2.0
> Multiple updates against same row/column/ts will be seen as increments to cache size
on insert but when we then play the memcache at flush time, we'll only see the most recent
entry and decrement the memcache size by whatever its size; memcache will be off.

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

View raw message