From user-return-37672-apmail-cassandra-user-archive=cassandra.apache.org@cassandra.apache.org Mon Nov 25 16:15:32 2013 Return-Path: X-Original-To: apmail-cassandra-user-archive@www.apache.org Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 02ABE109C2 for ; Mon, 25 Nov 2013 16:15:32 +0000 (UTC) Received: (qmail 94678 invoked by uid 500); 25 Nov 2013 16:15:26 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 94321 invoked by uid 500); 25 Nov 2013 16:15:23 -0000 Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@cassandra.apache.org Delivered-To: mailing list user@cassandra.apache.org Received: (qmail 94300 invoked by uid 99); 25 Nov 2013 16:15:22 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 25 Nov 2013 16:15:22 +0000 X-ASF-Spam-Status: No, hits=2.2 required=5.0 tests=HTML_MESSAGE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of artur.kronenberg@openmarket.com designates 81.187.36.3 as permitted sender) Received: from [81.187.36.3] (HELO puma.mxtelecom.com) (81.187.36.3) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 25 Nov 2013 16:15:17 +0000 Received: from glide.lon.openmarket.com ([10.9.64.115]) by puma.mxtelecom.com with esmtpsa (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.80.1) (envelope-from ) id 1VkyoJ-0000d5-VN for user@cassandra.apache.org; Mon, 25 Nov 2013 16:14:55 +0000 Message-ID: <5293777F.4090108@openmarket.com> Date: Mon, 25 Nov 2013 16:14:55 +0000 From: Artur Kronenberg User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.1 MIME-Version: 1.0 To: user@cassandra.apache.org Subject: Re: Nodetool cleanup References: In-Reply-To: Content-Type: multipart/alternative; boundary="------------000009060003080507040606" X-Virus-Checked: Checked by ClamAV on apache.org This is a multi-part message in MIME format. --------------000009060003080507040606 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hi Julien, I hope I get this right :) a repair will trigger a mayor compaction on your node which will take up a lot of CPU and IO performance. It needs to do this to build up the data structure that is used for the repair. After the compaction this is streamed to the different nodes in order to repair them. If you trigger this on every node simultaneously you basically take the performance away from your cluster. I would expect cassandra still to function, just way slower then before. Triggering it node after node will leave your cluster with more resources to handle incoming requests. Cheers, Artur On 25/11/13 15:12, Julien Campan wrote: > Hi, > > I'm working with Cassandra 1.2.2 and I have a question about nodetool > cleanup. > In the documentation , it's writted "Wait for cleanup to complete on > one node before doing the next" > > I would like to know, why we can't perform a lot of cleanup in a same > time ? > > > Thanks > > --------------000009060003080507040606 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit
Hi Julien,

I hope I get this right :)

a repair will trigger a mayor compaction on your node which will take up a lot of CPU and IO performance. It needs to do this to build up the data structure that is used for the repair. After the compaction this is streamed to the different nodes in order to repair them.

If you trigger this on every node simultaneously you basically take the performance away from your cluster. I would expect cassandra still to function, just way slower then before. Triggering it node after node will leave your cluster with more resources to handle incoming requests.


Cheers,

Artur
On 25/11/13 15:12, Julien Campan wrote:
Hi,

I'm working with Cassandra 1.2.2 and I have a question about nodetool cleanup.
In the documentation , it's writted " Wait for cleanup to complete on one node before doing the next"

I would like to know, why we can't perform a lot of cleanup in a same time ?


Thanks



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