Mailing-List: contact issues-help@hbase.apache.org; run by ezmlm
Precedence: bulk
Date: Fri, 17 Feb 2012 23:50:00 +0000 (UTC)
From: "Phabricator (Updated) (JIRA)" <jira@apache.org>
To: issues@hbase.apache.org
Message-ID: 
 <632039331.52681.1329522600825.JavaMail.tomcat@hel.zones.apache.org>
In-Reply-To: 
 <1326197391.10213.1328316713888.JavaMail.tomcat@hel.zones.apache.org>
Subject: [jira] [Updated] (HBASE-5332) Deterministic Compaction Jitter
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


     [ https://issues.apache.org/jira/browse/HBASE-5332?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Phabricator updated HBASE-5332:
-------------------------------

    Attachment: D1785.1.patch

nspiegelberg requested code review of "[jira] [HBASE-5332] Deterministic Compaction Jitter".
Reviewers: JIRA, Kannan, aaiyer, stack

  Changing the jitter in major compactions to be deterministic,
  so reboots don't cause a time-based compaction storm.  This
  implementation seeds a random number generator with HDFS data for
  persistence.

TEST PLAN
   - mvn test -Dtest=TestCompaction,TestCompactSelection,TestHeapSize

REVISION DETAIL
  https://reviews.facebook.net/D1785

AFFECTED FILES
  src/main/java/org/apache/hadoop/hbase/regionserver/Store.java
  src/test/java/org/apache/hadoop/hbase/regionserver/TestCompactSelection.java
  src/test/java/org/apache/hadoop/hbase/regionserver/TestCompaction.java

MANAGE HERALD DIFFERENTIAL RULES
  https://reviews.facebook.net/herald/view/differential/

WHY DID I GET THIS EMAIL?
  https://reviews.facebook.net/herald/transcript/3807/

Tip: use the X-Herald-Rules header to filter Herald messages in your client.

                
> Deterministic Compaction Jitter
> -------------------------------
>
>                 Key: HBASE-5332
>                 URL: https://issues.apache.org/jira/browse/HBASE-5332
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: Nicolas Spiegelberg
>            Assignee: Nicolas Spiegelberg
>            Priority: Minor
>         Attachments: D1785.1.patch
>
>
> Currently, we add jitter to a compaction using "delay + jitter*(1 - 2*Math.random())".  Since this is non-deterministic, we can get major compaction storms on server restart as half the Stores that were set to "delay + jitter" will now be set to "delay - jitter".  We need a more deterministic way to jitter major compactions so this information can persist across server restarts.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira