cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jeff Jirsa (JIRA)" <j...@apache.org>
Subject [jira] [Comment Edited] (CASSANDRA-10276) With DTCS, do STCS in windows if more than max_threshold sstables
Date Wed, 28 Oct 2015 06:52:27 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-10276?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14977863#comment-14977863
] 

Jeff Jirsa edited comment on CASSANDRA-10276 at 10/28/15 6:51 AM:
------------------------------------------------------------------

I'm definitely not disagreeing with you, but like always, the devil's in the details. If there
were 3 40MB files, 3 120M files, 3 500M files, 3 2G files, 3 8G files, and 3 24G files all
in one window, it might be nice to do one big rollup compaction (and that's a pretty extreme
example, but let's look at the edge cases, because someone's bound to hit it - one single
40M flush away from having a single 100G file in normal STCS operation, but in an old window,
that next 40M file may never show up, so we'll end up keeping 17 extra sstables around for
no reason).  


was (Author: jjirsa):
I'm definitely not disagreeing with you, but like always, the devil's in the details. If there
were 3 40MB files, 3 120M files, 3 500M files, 3 2G files, 3 8G files, and 3 24G files all
in one window, it might be nice to do one big rollup compaction (and that's a pretty extreme
example, but let's look at the edge cases, because someone's bound to hit it - one single
40M flush away from having a single 100G file in normal STCS operation).  

> With DTCS, do STCS in windows if more than max_threshold sstables
> -----------------------------------------------------------------
>
>                 Key: CASSANDRA-10276
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-10276
>             Project: Cassandra
>          Issue Type: Sub-task
>          Components: Core
>            Reporter: Marcus Eriksson
>            Assignee: Marcus Eriksson
>             Fix For: 3.x, 2.1.x, 2.2.x
>
>
> To avoid constant recompaction of files in big ( > max threshold) DTCS windows, we
should do STCS of those files.
> Patch here: https://github.com/krummas/cassandra/commits/marcuse/dtcs_stcs



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

Mime
View raw message