hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Virag Kothari (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-12016) Reduce number of versions in Meta table. Make it configurable
Date Fri, 19 Sep 2014 00:20:33 GMT

    [ https://issues.apache.org/jira/browse/HBASE-12016?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14139787#comment-14139787
] 

Virag Kothari commented on HBASE-12016:
---------------------------------------

bq. I can create static HTableDescriptor META_TABLEDESC back, just for compatibility and with
deprecation warning. HBase codebase will not use this instance. Does it sounds good?

Good for me. One  minor issue is if they query the HTableDescriptor.META_TABLEDESC for versions,
will they get 3 (the default)? Existing 0.98 deployments will have meta with 10 versions.
So, should we have 10 as default for 0.98?

bq. Does it sounds good, or we need to guarantee single instance of HTabelDescriptor across
vm?

I see what you are saying. Your approach looks good to me. Thanks for the explanation.



> Reduce number of versions in Meta table. Make it configurable
> -------------------------------------------------------------
>
>                 Key: HBASE-12016
>                 URL: https://issues.apache.org/jira/browse/HBASE-12016
>             Project: HBase
>          Issue Type: Improvement
>    Affects Versions: 2.0.0
>            Reporter: Andrey Stepachev
>            Assignee: Andrey Stepachev
>            Priority: Minor
>             Fix For: 2.0.0, 0.98.7, 0.99.1
>
>         Attachments: HBASE-12016.patch, HBASE-12016.patch
>
>
> Currently meta keeps up to 10 versions of each KV. 
> For big metas it leads to substantial memory overhead and scan slowdowns.
> (see https://issues.apache.org/jira/browse/HBASE-11165 )
> Need to keep reasonable number of versions (suggested value is 3). 
> Number of versions configurable via parameter: hbase.meta.versions



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message