From mboxrd@z Thu Jan 1 00:00:00 1970 From: mark delfman Subject: Re: xfs > md 50% write performance drop on .30+ kernel? Date: Tue, 13 Oct 2009 22:52:04 +0100 Message-ID: <66781b10910131452n10f6e1c3t5522fe0d56a187b@mail.gmail.com> References: <66781b10910120958k4afb637ejba79e4c23900c4da@mail.gmail.com> <4AD3F64F.6070908@sauce.co.nz> <4AD454A0.3050704@shiftmail.org> <4AD4DAA4.4080703@sauce.co.nz> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <4AD4DAA4.4080703@sauce.co.nz> Sender: linux-raid-owner@vger.kernel.org To: Richard Scobie Cc: Asdo , linux-raid List-Id: linux-raid.ids This is the same experience we have, without a doubt the =91dumb=92 LSI SAS cards + MD are certainly faster and more flexible (actually, I should say MD is faster and more flexible). The LSI SAS2 chips scale up better via the expanders (even if the expanders / drives are SAS1) BUT =96 problem with all this performance, is it is disappointing when we lose it on XFS :( On Tue, Oct 13, 2009 at 8:53 PM, Richard Scobie w= rote: > Asdo wrote: > >> Do you think it was controller's overhead? I have heard mixed opinio= ns >> about 3wares. What are the fastest controllers around for MD-raid us= e? > > The fastest setup I have found have been LSI SAS cards - LSISAS3442E-= R, with > the onboard RAID firmware replaced with the IT firmware. > > This is connected to port expander based JBOD chassis loaded with eit= her > =A0SAS or SATA drives. > > Regards, > > Richard > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > -- 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