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https://issues.apache.org/jira/browse/HBASE-5778?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13252976#comment-13252976
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Hudson commented on HBASE-5778:
-------------------------------

Integrated in HBase-TRUNK #2749 (See 
[https://builds.apache.org/job/HBase-TRUNK/2749/])
    HBASE-5778  Turn on WAL compression by default (Revision 1325566)

     Result = FAILURE
jdcryans : 
Files : 
* 
/hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SequenceFileLogWriter.java

                
> Turn on WAL compression by default
> ----------------------------------
>
>                 Key: HBASE-5778
>                 URL: https://issues.apache.org/jira/browse/HBASE-5778
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: Jean-Daniel Cryans
>            Assignee: Jean-Daniel Cryans
>            Priority: Blocker
>             Fix For: 0.94.0, 0.96.0
>
>         Attachments: HBASE-5778.patch
>
>
> I ran some tests to verify if WAL compression should be turned on by default.
> For a use case where it's not very useful (values two order of magnitude 
> bigger than the keys), the insert time wasn't different and the CPU usage 15% 
> higher (150% CPU usage VS 130% when not compressing the WAL).
> When values are smaller than the keys, I saw a 38% improvement for the insert 
> run time and CPU usage was 33% higher (600% CPU usage VS 450%). I'm not sure 
> WAL compression accounts for all the additional CPU usage, it might just be 
> that we're able to insert faster and we spend more time in the MemStore per 
> second (because our MemStores are bad when they contain tens of thousands of 
> values).
> Those are two extremes, but it shows that for the price of some CPU we can 
> save a lot. My machines have 2 quads with HT, so I still had a lot of idle 
> CPUs.

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