Return-Path: Delivered-To: apmail-cassandra-commits-archive@www.apache.org Received: (qmail 43817 invoked from network); 7 Jul 2010 20:39:16 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 7 Jul 2010 20:39:16 -0000 Received: (qmail 9399 invoked by uid 500); 7 Jul 2010 20:39:16 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 9374 invoked by uid 500); 7 Jul 2010 20:39:15 -0000 Mailing-List: contact commits-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@cassandra.apache.org Delivered-To: mailing list commits@cassandra.apache.org Received: (qmail 9366 invoked by uid 99); 7 Jul 2010 20:39:15 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 07 Jul 2010 20:39:15 +0000 X-ASF-Spam-Status: No, hits=-2000.0 required=10.0 tests=ALL_TRUSTED X-Spam-Check-By: apache.org Received: from [140.211.11.22] (HELO thor.apache.org) (140.211.11.22) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 07 Jul 2010 20:39:13 +0000 Received: from thor (localhost [127.0.0.1]) by thor.apache.org (8.13.8+Sun/8.13.8) with ESMTP id o67KcpPD004696 for ; Wed, 7 Jul 2010 20:38:51 GMT Message-ID: <19351166.245381278535131446.JavaMail.jira@thor> Date: Wed, 7 Jul 2010 16:38:51 -0400 (EDT) From: "Jonathan Ellis (JIRA)" To: commits@cassandra.apache.org Subject: [jira] Commented: (CASSANDRA-1181) kinder gentler compaction In-Reply-To: <16518379.36161276215555982.JavaMail.jira@thor> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 X-Virus-Checked: Checked by ClamAV on apache.org [ https://issues.apache.org/jira/browse/CASSANDRA-1181?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12886068#action_12886068 ] Jonathan Ellis commented on CASSANDRA-1181: ------------------------------------------- Thanks for trying it out! > kinder gentler compaction > ------------------------- > > Key: CASSANDRA-1181 > URL: https://issues.apache.org/jira/browse/CASSANDRA-1181 > Project: Cassandra > Issue Type: Task > Components: Core > Reporter: Jonathan Ellis > Assignee: Jonathan Ellis > Fix For: 0.6.3 > > Attachments: 1181.txt, CompactionManager.java, stats.txt > > > I suggested this in a ML thread but it seems that nobody actually tried it. I think it's worth following up on: > You could try setting the compaction thread to a lower priority. You could add a thread priority to NamedThreadPool, and pass that up from CompactionExecutor constructor. According to http://www.javamex.com/tutorials/threads/priority_what.shtml you have to run as root and add a JVM option to get this to work. > In particular, Brandon saw stress.py read latencies spike to 100ms during [anti]compaction on a 2 core machine. I'd like to see if this can mitigate that. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.