cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Marcus Eriksson (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CASSANDRA-12366) Fix compaction throttle
Date Wed, 03 Aug 2016 09:08:20 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-12366?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15405602#comment-15405602
] 

Marcus Eriksson commented on CASSANDRA-12366:
---------------------------------------------

LGTM, just one minor comment;

in {{AbstractCompactionStrategy#getCurrentCompressionRatio()}} - should it calculate the average
compression ratio instead of just getting the compression ratio for the last sstable - maybe
we could use {{TableMetrics#computeCompressionRatio(Iterable<SSTableReader>...)}}?

> Fix compaction throttle
> -----------------------
>
>                 Key: CASSANDRA-12366
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-12366
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Compaction
>            Reporter: T Jake Luciani
>            Assignee: T Jake Luciani
>             Fix For: 3.x
>
>
> Compaction throttling is broken in the following ways:
>   * It throttles bytes read after being decompressed
>   * Compaction creates multiple scanners which share the rate limiter causing too much
throttling
>   * It bears no resemblance to the reported compaction time remaining calculation (Bytes
of source sstables processed since start of compaction)
> To fix this we need to simplify the throttling to be only at the CompactionIterator level.



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

Mime
View raw message