Mailing-List: contact notifications-help@accumulo.apache.org; run by ezmlm
Precedence: bulk
Reply-To: jira@apache.org
Date: Fri, 5 Oct 2012 20:00:04 +0000 (UTC)
From: "Eric Newton (JIRA)" <jira@apache.org>
To: notifications@accumulo.apache.org
Message-ID: <2054006370.2431.1349467204231.JavaMail.jiratomcat@arcas>
In-Reply-To: <597665784.1049.1349447042673.JavaMail.jiratomcat@arcas>
Subject: [jira] [Commented] (ACCUMULO-786) Look into walog space usage
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


    [ https://issues.apache.org/jira/browse/ACCUMULO-786?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13470607#comment-13470607 ] 

Eric Newton commented on ACCUMULO-786:
--------------------------------------

I got the 36 bytes down to 11, for small entries, and performed some tests writing write-ahead logs.  I'm seeing a 10-20% improvement in write speed.  I am not seeing much of an improvement in ContinuousIngest, however.

In addition, I'm using a system timestamp in Mutation, which is separate from the timestamp in the serialized ColumnUpdate.  That means the tablet server isn't deserializing the ColumnUpdates just to set the timestamps.  That will save the work of creating lots of small objects, just to throw them all away.

                
> Look into walog space usage
> ---------------------------
>
>                 Key: ACCUMULO-786
>                 URL: https://issues.apache.org/jira/browse/ACCUMULO-786
>             Project: Accumulo
>          Issue Type: Task
>            Reporter: Keith Turner
>             Fix For: 1.5.0
>
>
> I was experimenting with write ahead log write performance and noticed that when I wrote 1G of data that the walog was 1.5G.

--
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