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Posted to commits@cassandra.apache.org by "Stu Hood (Created) (JIRA)" <ji...@apache.org> on 2012/02/05 22:53:59 UTC

[jira] [Created] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

RemoveDeleted dominates compaction time for large sstable counts
----------------------------------------------------------------

                 Key: CASSANDRA-3855
                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
             Project: Cassandra
          Issue Type: Bug
          Components: Core
    Affects Versions: 1.1
            Reporter: Stu Hood
            Priority: Critical
         Attachments: with-cleaning-java.hprof.txt

With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.

Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Hudson (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13419677#comment-13419677 ] 

Hudson commented on CASSANDRA-3855:
-----------------------------------

Integrated in Cassandra #1734 (See [https://builds.apache.org/job/Cassandra/1734/])
    fix incorrect hasIrrelevantData result for live CF; patch by yukim, reviewed by jbellis/slebresne for CASSANDRA-3855 (Revision d74103735126658d64cb92a16f4bb40f63d5e2e8)

     Result = ABORTED
yukim : 
Files : 
* src/java/org/apache/cassandra/db/AbstractColumnContainer.java

                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>             Fix For: 1.2
>
>         Attachments: 3855.txt, with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Updated] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Stu Hood (Updated) (JIRA)" <ji...@apache.org>.
     [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Stu Hood updated CASSANDRA-3855:
--------------------------------

    Attachment: with-cleaning-java.hprof.txt
    
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1
>            Reporter: Stu Hood
>            Priority: Critical
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Sylvain Lebresne (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13419180#comment-13419180 ] 

Sylvain Lebresne commented on CASSANDRA-3855:
---------------------------------------------

Your right, that's a broken optimization, the 2 first lines should be removed.
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Jonathan Ellis (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13419183#comment-13419183 ] 

Jonathan Ellis commented on CASSANDRA-3855:
-------------------------------------------

+1 for proposed method w/ first 2 lines removed
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Updated] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Yuki Morishita (JIRA)" <ji...@apache.org>.
     [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Yuki Morishita updated CASSANDRA-3855:
--------------------------------------

    Attachment: 3855.txt

So I summarized and attached patch. Tested on trunk and confirmed it fixed.
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: 3855.txt, with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Resolved] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Yuki Morishita (JIRA)" <ji...@apache.org>.
     [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Yuki Morishita resolved CASSANDRA-3855.
---------------------------------------

       Resolution: Fixed
    Fix Version/s: 1.2
         Reviewer: jbellis

Committed to trunk.
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>             Fix For: 1.2
>
>         Attachments: 3855.txt, with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Yuki Morishita (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13418759#comment-13418759 ] 

Yuki Morishita commented on CASSANDRA-3855:
-------------------------------------------

I ran cpu profile on trunk and 1.1 with LCS and about 1000 sstables. On 1.1 branch, there is no indication of dominating removeDeletedAndOldShards. But for trunk, I noticed that it seemed unnecessary CompactionController#shouldPurge is called inside removeDeletedAndOldShards, where shouldPurge is supposed to be called only when CF has tombstones. So I looked up the code and I'm not sure if this line(https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/AbstractColumnContainer.java#L201) is correct. If CF is live, returning false for hasIrrelevantData seems right. Sylvain, what do you think?
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Updated] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Jonathan Ellis (JIRA)" <ji...@apache.org>.
     [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Jonathan Ellis updated CASSANDRA-3855:
--------------------------------------

    Assignee: Yuki Morishita  (was: Sylvain Lebresne)

Yuki, can you benchmark trunk and see if this is still a bottleneck?  I think we want to bench both LCS and STCS.
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Jonathan Ellis (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13419177#comment-13419177 ] 

Jonathan Ellis commented on CASSANDRA-3855:
-------------------------------------------

We definitely don't want "if row is live, nothing to do here" behavior, otherwise we'll never purge column-level tombstones without a full row deletion.
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Assigned] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Sylvain Lebresne (Assigned) (JIRA)" <ji...@apache.org>.
     [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Sylvain Lebresne reassigned CASSANDRA-3855:
-------------------------------------------

    Assignee: Sylvain Lebresne
    
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1
>            Reporter: Stu Hood
>            Assignee: Sylvain Lebresne
>            Priority: Critical
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Sylvain Lebresne (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13419006#comment-13419006 ] 

Sylvain Lebresne commented on CASSANDRA-3855:
---------------------------------------------

Agreed that it is wrong, but I think that it's more than the first line that is wrong. I think that method should be:
{noformat}
public boolean hasIrrelevantData(int gcBefore)
{
    if (deletionInfo().isLive())
        return false;

    // Do we have gcable deletion infos?
    if (!deletionInfo().purge(gcbefore).equals(deletionInfo()))
        return true;

    // Do we have colums that are either deleted by the container or gcable tombstone?
    for (IColumn column : columns)
        if (deletionInfo().isDeleteted(column) || column.hasIrrelevantData(gcBefore))
            return true;

    return false;
}
{noformat}
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Jonathan Ellis (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13418775#comment-13418775 ] 

Jonathan Ellis commented on CASSANDRA-3855:
-------------------------------------------

That's definitely wrong...  I think it should be {{if (info != LIVE) return false}}
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Sylvain Lebresne (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13295818#comment-13295818 ] 

Sylvain Lebresne commented on CASSANDRA-3855:
---------------------------------------------

I'll precise that I try to do a quick test to see if I could reproduce "back in the days" but wasn't really able to reproduce something similar to the attached hprof log. I didn't wait up to 100,000,000 keys though.
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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[jira] [Commented] (CASSANDRA-3855) RemoveDeleted dominates compaction time for large sstable counts

Posted by "Jonathan Ellis (JIRA)" <ji...@apache.org>.
    [ https://issues.apache.org/jira/browse/CASSANDRA-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13419352#comment-13419352 ] 

Jonathan Ellis commented on CASSANDRA-3855:
-------------------------------------------

+1
                
> RemoveDeleted dominates compaction time for large sstable counts
> ----------------------------------------------------------------
>
>                 Key: CASSANDRA-3855
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-3855
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Stu Hood
>            Assignee: Yuki Morishita
>              Labels: compaction, deletes, leveled
>         Attachments: 3855.txt, with-cleaning-java.hprof.txt
>
>
> With very large numbers of sstables (2000+ generated by a `bin/stress -n 100,000,000` run with LeveledCompactionStrategy), PrecompactedRow.removeDeletedAndOldShards dominates compaction runtime, such that commenting it out takes compaction throughput from 200KB/s to 12MB/s.
> Stack attached.

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