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https://issues.apache.org/jira/browse/HBASE-3189?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12928122#action_12928122
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Kannan Muthukkaruppan commented on HBASE-3189:
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I think, usability wise, jitter (and it's default) should be specified as 
fraction (% value) of the major compaction cycle time, instead of absolute 
terms (like 4 hours)/

Otherwise, you have a backward compat issue with this change for someone who is 
running a major compaction say every three hours, but has forgotten to set the 
jitter parameter when they upgrade to 0.90. And they'll be compacting anywhere 
from 3hrs +/- (2* 4 hours jitter default). This approach will also ensure you 
don't return -ve values for "get next compaction time".


> Stagger Major Compactions
> -------------------------
>
>                 Key: HBASE-3189
>                 URL: https://issues.apache.org/jira/browse/HBASE-3189
>             Project: HBase
>          Issue Type: Bug
>          Components: regionserver
>            Reporter: Nicolas Spiegelberg
>            Assignee: Nicolas Spiegelberg
>            Priority: Minor
>             Fix For: 0.90.0
>
>         Attachments: HBASE-3189.patch
>
>
> For pre-split regions, we can get into a case where the oldest HFile in a 
> Store is pretty large and will not encounter a compaction within the 24hr 
> major compact window.  If that's the case, we don't want multiple multi-GB 
> major compactions being triggered at the same time.  Add ability to stagger 
> the major compaction expiration window.

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