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HBase Review Board commented on HBASE-2468: ------------------------------------------- Message from: "Ryan Rawson" <ryano...@gmail.com> > 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 -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.