Return-Path: X-Original-To: apmail-cassandra-commits-archive@www.apache.org Delivered-To: apmail-cassandra-commits-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 914E017C8A for ; Thu, 23 Oct 2014 23:16:34 +0000 (UTC) Received: (qmail 93628 invoked by uid 500); 23 Oct 2014 23:16:34 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 93594 invoked by uid 500); 23 Oct 2014 23:16:34 -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 93298 invoked by uid 99); 23 Oct 2014 23:16:34 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 23 Oct 2014 23:16:34 +0000 Date: Thu, 23 Oct 2014 23:16:34 +0000 (UTC) From: "Sean Bridges (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (CASSANDRA-8177) sequential repair is much more expensive than parallel repair 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-8177?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14182157#comment-14182157 ] Sean Bridges commented on CASSANDRA-8177: ----------------------------------------- We can't easily upgrade to 2.1. I don't think this issue is a dupe of CASSANDRA-5220. Looking at the graphs, I think something is quite wrong with sequential or parallel repair. With a 3 node cluster, using sequential shouldn't cause repairs to take 13 times as long, and use a lot more io. > sequential repair is much more expensive than parallel repair > ------------------------------------------------------------- > > Key: CASSANDRA-8177 > URL: https://issues.apache.org/jira/browse/CASSANDRA-8177 > Project: Cassandra > Issue Type: Bug > Reporter: Sean Bridges > Attachments: iostats.png > > > This is with 2.0.10 > The attached graph shows io read/write throughput (as measured with iostat) when doing repairs. > The large hump on the left is a sequential repair of one node. The two much smaller peaks on the right are parallel repairs. > This is a 3 node cluster using vnodes (I know vnodes on small clusters isn't recommended). Cassandra reports load of 40 gigs. > We noticed a similar problem with a larger cluster. -- This message was sent by Atlassian JIRA (v6.3.4#6332)