[ https://issues.apache.org/jira/browse/HBASE-3976?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Lars Hofhansl resolved HBASE-3976. ---------------------------------- Resolution: Fixed Closing... Please reopen if this should be kept open. > Disable Block Cache On Compactions > ---------------------------------- > > Key: HBASE-3976 > URL: https://issues.apache.org/jira/browse/HBASE-3976 > Project: HBase > Issue Type: Improvement > Components: regionserver > Affects Versions: 0.90.3 > Reporter: Karthick Sankarachary > Assignee: Mikhail Bautin > Priority: Minor > Attachments: HBASE-3976.patch, HBASE-3976-unconditional.patch, > HBASE-3976-V3.patch > > > Is there a good reason to believe that caching blocks during compactions is > beneficial? Currently, if block cache is enabled on a certain family, then > every time it's compacted, we load all of its blocks into the (LRU) cache, at > the expense of the legitimately hot ones. > As a matter of fact, this concern was raised earlier in HBASE-1597, which > rightly points out that, "we should not bog down the LRU with unneccessary > blocks" during compaction. Even though that issue has been marked as "fixed", > it looks like it ought to be reopened. > Should we err on the side of caution and not cache blocks during compactions > period (as illustrated in the attached patch)? Or, can we be selectively > aggressive about what blocks do get cached during compaction (e.g., only > cache those blocks from the recent files)? -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira