[jira] [Commented] (HBASE-16755) Honor flush policy under global memstore pressure

["Gary Helmling (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HBASE-16755?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15887056#comment-15887056 ] 

Gary Helmling commented on HBASE-16755:
---------------------------------------

+1 on the patch.

Since we have both FlushLargeStoresPolicy and FlushAllStoresPolicy (and more options in master), makes sense to me to honor that policy, even under global memstore pressure.

[~Apache9] any thoughts on this change, since you ported over the per-store flush decisions originally?  We've seen situations where, due to hitting global memstore pressure, we constantly flush lots of small files, even when stores are eligible to flush with FlushLargeStoresPolicy.

> Honor flush policy under global memstore pressure
> -------------------------------------------------
>
>                 Key: HBASE-16755
>                 URL: https://issues.apache.org/jira/browse/HBASE-16755
>             Project: HBase
>          Issue Type: Improvement
>          Components: regionserver
>            Reporter: Ashu Pachauri
>            Assignee: Ashu Pachauri
>             Fix For: 1.3.1
>
>         Attachments: HBASE-16755.v0.patch
>
>
> When global memstore reaches the low water mark, we pick the best flushable region and flush all column families for it. This is a suboptimal approach in the  sense that it leads to an unnecessarily high file creation rate and IO amplification due to compactions. We should still try to honor the underlying FlushPolicy.



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)