From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Nelson Subject: Re: FS / Kernel question choosing the correct kernel version Date: Tue, 26 Jun 2012 11:59:49 -0500 Message-ID: <4FE9EA85.9030809@inktank.com> References: <4FE60A65.2030800@profihost.ag> <4FE97BE8.6010603@profihost.ag> <4FE9E006.6030404@profihost.ag> <4FE9E360.8050807@inktank.com> <4FE9E6CB.8080803@profihost.ag> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-yw0-f51.google.com ([209.85.213.51]:40807 "EHLO mail-yw0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758348Ab2FZRAG (ORCPT ); Tue, 26 Jun 2012 13:00:06 -0400 Received: by yhnn12 with SMTP id n12so176823yhn.10 for ; Tue, 26 Jun 2012 10:00:06 -0700 (PDT) In-Reply-To: <4FE9E6CB.8080803@profihost.ag> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Stefan Priebe Cc: Sage Weil , "ceph-devel@vger.kernel.org" , "hch@infradead.org >> Christoph Hellwig" On 06/26/2012 11:43 AM, Stefan Priebe wrote: > Am 26.06.2012 18:29, schrieb Mark Nelson: >> On 06/26/2012 11:15 AM, Stefan Priebe wrote: >> Hi Stefan, >> >> If you can, it would be really interesting to see the blktrace results >> during these tests for both xfs and btrfs. blktrace is in the ubuntu >> repositories and can be run quite easily from the command line during >> your test. > > Sure any special parameters? I have 4 SSDs per OSD Server. > > Or just blktrace -o file? > > Stefan For each device you run it on you'll get one file per core. There may be some performance impact if you run blktrace on every device per node. If your data is well distributed, even a trace for one OSD (per test) would be interesting. so blktrace -o -d where device is your first OSD or something. If you can do it for both btrfs and xfs and maybe run each test for a couple of minutes that might be enough. Mark