From commits-return-19773-apmail-cassandra-commits-archive=cassandra.apache.org@cassandra.apache.org Fri Oct 01 16:18:57 2010 Return-Path: Delivered-To: apmail-cassandra-commits-archive@www.apache.org Received: (qmail 21131 invoked from network); 1 Oct 2010 16:18:57 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 1 Oct 2010 16:18:57 -0000 Received: (qmail 36685 invoked by uid 500); 1 Oct 2010 16:18:57 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 36659 invoked by uid 500); 1 Oct 2010 16:18:56 -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 36651 invoked by uid 99); 1 Oct 2010 16:18:56 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 01 Oct 2010 16:18:56 +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; Fri, 01 Oct 2010 16:18:55 +0000 Received: from thor (localhost [127.0.0.1]) by thor.apache.org (8.13.8+Sun/8.13.8) with ESMTP id o91GIYxD023494 for ; Fri, 1 Oct 2010 16:18:35 GMT Message-ID: <25785906.499321285949914858.JavaMail.jira@thor> Date: Fri, 1 Oct 2010 12:18:34 -0400 (EDT) From: "Jonathan Ellis (JIRA)" To: commits@cassandra.apache.org Subject: [jira] Commented: (CASSANDRA-1526) Make cassandra sampling and startup faster In-Reply-To: <15972528.321171285090414185.JavaMail.jira@thor> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/CASSANDRA-1526?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12916935#action_12916935 ] Jonathan Ellis commented on CASSANDRA-1526: ------------------------------------------- the pause is where the executor is finishing the actual indexing :) i think 1526.txt is as good as we're likely to get for 0.6. 0.7 simplifies the indexing in a couple ways that should let us skip the decoding Stu mentioned and do a more effective job parallelizing per-CF. > Make cassandra sampling and startup faster > ------------------------------------------ > > Key: CASSANDRA-1526 > URL: https://issues.apache.org/jira/browse/CASSANDRA-1526 > Project: Cassandra > Issue Type: Improvement > Components: Core > Reporter: Edward Capriolo > Assignee: Stu Hood > Priority: Minor > Fix For: 0.6.7, 0.7.0 > > Attachments: 0.6-0001-Add-AggregateFuture-to-wait-for-a-batch-of-futures-a.patch, 0.6-0002-Parallelize-SSTable-open.patch, 1526.txt, cpu.txt, io.txt, snitcherror.txt > > > http://wiki.apache.org/cassandra/CassandraHardware makes mention of very large disks I do not see how that would be possible. > We have a server class system have 4x processors 16GB RAM a 6 DISK RAID5 (yes RAID0 would be faster but still) > {noformat} > INFO [main] 2010-09-21 12:58:26,348 SSTableReader.java (line 120) Sampling index for /var/lib/cassandra/data/system/LocationInfo-699-Data.db > ... > INFO [main] 2010-09-21 13:05:51,333 CassandraDaemon.java (line 124) Binding thrift service to cdbsd07/10.71.71.57:9160 > {noformat} > This node has 200GB of data in two column families and the time to sample all tables and startup is 7+ minutes. The logging suggests this process is happening a single SSTable at a time. Additionally the normal system vitals mainly DISK and CPU do not look overtaxed. > * Since SSTables are immutable is there a way the sampling of the tables could be saved? > * Could this process be done in parallel for speedup? > * Can multiple column families be processed at once? > Unless someone has an insanely powerful disk pack making mention of 2TB limitations seem out of place. Unless my calculations are wrong (which they usually are), I have a pretty decent hardware, and if I had 2 TB of data I would have a 95 minute node start up? > I hope that maybe sampling multiple ColumnFamilies at once would make nodes of at least a few hundred GB startup reasonably fast. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.