From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keld =?iso-8859-1?Q?J=F8rn?= Simonsen Subject: Re: Awful Raid10,f2 performance Date: Tue, 16 Dec 2008 23:01:47 +0100 Message-ID: <20081216220147.GA22148@rap.rap.dk> References: <48440953.3040004@wpkg.org> <18758.52823.375213.963854@notabene.brown> <20081216040349.GA15389@rap.rap.dk> <20081216101020.GA17410@rap.rap.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Jon Nelson Cc: Neil Brown , Linux-Raid List-Id: linux-raid.ids On Tue, Dec 16, 2008 at 09:53:39AM -0600, Jon Nelson wrote: > On Tue, Dec 16, 2008 at 9:26 AM, Jon Nelson > wrote: > > On Tue, Dec 16, 2008 at 4:10 AM, Keld J=F8rn Simonsen wrote: > >> On Mon, Dec 15, 2008 at 10:28:30PM -0600, Jon Nelson wrote: > >>> On Mon, Dec 15, 2008 at 10:03 PM, Keld J=F8rn Simonsen wrote: > >>> > >>> > there was a pach to speed up raid10,f2 check in a recent kernel= , > >>> > something like 2.6.27. It did improve thruput from something > >>> > like 40 % to about 90 %. What kernel are you using? > >>> > >>> 2.6.25.18-0.2-default > >> > >> I believe the patch arrived in a later kernel. If you can try it o= ut > >> with a vanilla kernel and report, I think it would be quite intere= sting. > > > > I'm pretty sure I did try it out and did have an improvement. > > However, thanks to the power of the openSUSE build service, I am go= ing > > to build a kernel just now, if I can. >=20 > Scratch that. I decided to just do this at home. The suse kernel > 2.6.25.18-0.2 appears to have this patch already. Thus, I've been > running with this patch. OK, well, then the patch did not apply to check, but only to resync. One could write up a similar patch for check as what was done for resync. The idea of the previous patch was to read quite much data in a striped way, say 10 - 20 MB at a time. best regards keld -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html