From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Nelson Subject: Re: massive rbd speed decrease with latest git master Date: Mon, 05 Nov 2012 12:58:44 -0600 Message-ID: <50980C64.8050501@inktank.com> References: <50979779.3040300@profihost.ag> <50980A0C.7010200@profihost.ag> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ie0-f174.google.com ([209.85.223.174]:51877 "EHLO mail-ie0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750915Ab2KES6o (ORCPT ); Mon, 5 Nov 2012 13:58:44 -0500 Received: by mail-ie0-f174.google.com with SMTP id k13so8492357iea.19 for ; Mon, 05 Nov 2012 10:58:43 -0800 (PST) In-Reply-To: <50980A0C.7010200@profihost.ag> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Stefan Priebe Cc: "ceph-devel@vger.kernel.org" , alexandre DERUMIER On 11/05/2012 12:48 PM, Stefan Priebe wrote: > Am 05.11.2012 11:39, schrieb Stefan Priebe - Profihost AG: >> Hello list, >> >> while updating ceph to the latest master i noticed this: >> >> Commit a01b112d71a0b6a1bb206d53867d13536d17bbf6: >> rand. 4k WRITE: 3000 iop/s >> >> Commit 72a710ac47355ae3ca1d055be1496c91956d549d: >> rand. 4k WRITE: 900 iop/s >> >> Same for rand 4k read - haven't tested sequential stuff. > > OK i found out what the issue is. I get 900 iop/s when compiled with > syncfs support and i get 3000-6000 iop/s when compiled without syncfs > support. > > Strange shouldn't syncfs improve the performance? > > Note: ceph is running inside KVM right now for testing with an iscsi > based backend storage. My real testhw will arrive tomorrow. Very strange. I'm curious if you continue to see this on your real test hardware. > > Greets, > Stefan > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Mark