From mboxrd@z Thu Jan 1 00:00:00 1970 From: Justin Piszcz Subject: Re: Kernel 2.6.19.2 New RAID 5 Bug (oops when writing Samba -> RAID5) Date: Tue, 23 Jan 2007 08:46:48 -0500 (EST) Message-ID: References: <45B5261B.1050104@redhat.com> <17845.13256.284461.992275@notabene.brown> <45B5ECAA.6000100@tls.msk.ru> <45B60403.1060201@tls.msk.ru> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: <45B60403.1060201@tls.msk.ru> Sender: linux-raid-owner@vger.kernel.org To: Michael Tokarev Cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, xfs@oss.sgi.com, Alan Piszcz List-Id: linux-raid.ids On Tue, 23 Jan 2007, Michael Tokarev wrote: > Justin Piszcz wrote: > > > > On Tue, 23 Jan 2007, Michael Tokarev wrote: > > > >> Disabling pre-emption on critical and/or server machines seems to be a good > >> idea in the first place. IMHO anyway.. ;) > > > > So bottom line is make sure not to use preemption on servers or else you > > will get weird spinlock/deadlocks on RAID devices--GOOD To know! > > This is not a reason. The reason is that preemption usually works worse > on servers, esp. high-loaded servers - the more often you interrupt a > (kernel) work, the more nedleess context switches you'll have, and the > more slow the whole thing works. > > Another point is that with preemption enabled, we have more chances to > hit one or another bug somewhere. Those bugs should be found and fixed > for sure, but important servers/data isn't a place usually for bughunting. > > /mjt > - > 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 http://vger.kernel.org/majordomo-info.html > Thanks for the update/info. Justin.