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https://issues.apache.org/jira/browse/HBASE-2468?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12878103#action_12878103
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Mingjie Lai commented on HBASE-2468:
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@stack: Yes, I will create another patch. But before that, I still need to 
finish the discussion about where to put the static method 
HTable.setRegionCachePrefetch(table, enable). After we make an agreement it, I 
will generate a new patch right away.

> Improvements to prewarm META cache on clients
> ---------------------------------------------
>
>                 Key: HBASE-2468
>                 URL: https://issues.apache.org/jira/browse/HBASE-2468
>             Project: HBase
>          Issue Type: Improvement
>          Components: client
>            Reporter: Todd Lipcon
>            Assignee: Mingjie Lai
>             Fix For: 0.21.0
>
>         Attachments: HBASE-2468-trunk.patch
>
>
> A couple different use cases cause storms of reads to META during startup. 
> For example, a large MR job will cause each map task to hit meta since it 
> starts with an empty cache.
> A couple possible improvements have been proposed:
>  - MR jobs could ship a copy of META for the table in the DistributedCache
>  - Clients could prewarm cache by doing a large scan of all the meta for the 
> table instead of random reads for each miss
>  - Each miss could fetch ahead some number of rows in META

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