Mailing-List: contact commits-help@cassandra.apache.org; run by ezmlm
Precedence: bulk
Reply-To: dev@cassandra.apache.org
Message-ID: <30799475.135781289960835261.JavaMail.jira@thor>
Date: Tue, 16 Nov 2010 21:27:15 -0500 (EST)
From: "T Jake Luciani (JIRA)" <jira@apache.org>
To: commits@cassandra.apache.org
Subject: [jira] Updated: (CASSANDRA-1470) use direct io for compaction
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


     [ https://issues.apache.org/jira/browse/CASSANDRA-1470?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

T Jake Luciani updated CASSANDRA-1470:
--------------------------------------

    Attachment: CASSANDRA-1470-v10-for-0.7.patch

Next patch iteration,

1) Removed dependency on JNA.  Required reflection to check for JNA exception types at runtime.
2) BRAF was calling fsync() on every write.  added separate flush() and sync() calls. reBuffer calls flush() rather than sync().

Next issue occurs when running compaction with directIO, the compaction thread seems to get stuck 
in the rebuffer channel.read() call.  I think it's todo with the alignment but need to dig in deeper tomorrow.


> use direct io for compaction
> ----------------------------
>
>                 Key: CASSANDRA-1470
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-1470
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>            Reporter: Jonathan Ellis
>            Assignee: Pavel Yaskevich
>             Fix For: 0.6.9
>
>         Attachments: 1470-v2.txt, 1470.txt, CASSANDRA-1470-for-0.6.patch, CASSANDRA-1470-v10-for-0.7.patch, CASSANDRA-1470-v2.patch, CASSANDRA-1470-v3-0.7-with-LastErrorException-support.patch, CASSANDRA-1470-v4-for-0.7.patch, CASSANDRA-1470-v5-for-0.7.patch, CASSANDRA-1470-v6-for-0.7.patch, CASSANDRA-1470-v7-for-0.7.patch, CASSANDRA-1470-v8-for-0.7.patch, CASSANDRA-1470-v9-for-0.7.patch, CASSANDRA-1470.patch, use.DirectIORandomAccessFile.for.commitlog.against.1022235.patch
>
>
> When compaction scans through a group of sstables, it forces the data in the os buffer cache being used for hot reads, which can have a dramatic negative effect on performance.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.