hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Lars Hofhansl (JIRA)" <j...@apache.org>
Subject [jira] [Resolved] (HBASE-3976) Disable Block Cache On Compactions
Date Wed, 05 Sep 2012 17:54:09 GMT

     [ 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

Mime
View raw message