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https://issues.apache.org/jira/browse/HBASE-15324?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15652810#comment-15652810
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Esteban Gutierrez commented on HBASE-15324:
-------------------------------------------

[~huaxiang] I think the problem is the value of the epsilon used for the 
precision of the types involved (float x double).  I think it should be at 
least 2.22e-16 (2^-52) or even 1.11e-16 (2^-53).  Created HBASE-17058 for 
follow up. Thanks.

> Jitter may cause desiredMaxFileSize overflow in ConstantSizeRegionSplitPolicy 
> and trigger unexpected split
> ----------------------------------------------------------------------------------------------------------
>
>                 Key: HBASE-15324
>                 URL: https://issues.apache.org/jira/browse/HBASE-15324
>             Project: HBase
>          Issue Type: Bug
>    Affects Versions: 2.0.0, 1.1.3
>            Reporter: Yu Li
>            Assignee: Yu Li
>             Fix For: 2.0.0, 1.3.0, 1.4.0, 1.2.5, 1.1.8
>
>         Attachments: HBASE-15324.patch, HBASE-15324_v2.patch, 
> HBASE-15324_v3.patch, HBASE-15324_v3.patch
>
>
> We introduce jitter for region split decision in HBASE-13412, but the 
> following line in {{ConstantSizeRegionSplitPolicy}} may cause long value 
> overflow if MAX_FILESIZE is specified to Long.MAX_VALUE:
> {code}
> this.desiredMaxFileSize += (long)(desiredMaxFileSize * (RANDOM.nextFloat() - 
> 0.5D) * jitter);
> {code}
> In our case we specify MAX_FILESIZE to Long.MAX_VALUE to prevent target 
> region to split.



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