From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 14 Jun 2003 23:20:49 -0700 From: Andrew Morton Subject: Re: 2.5.70-mm9 Message-Id: <20030614232049.6610120d.akpm@digeo.com> In-Reply-To: <1055637690.1396.15.camel@w-ming2.beaverton.ibm.com> References: <20030613013337.1a6789d9.akpm@digeo.com> <3EEAD41B.2090709@us.ibm.com> <20030614010139.2f0f1348.akpm@digeo.com> <1055637690.1396.15.camel@w-ming2.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Mingming Cao Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: Mingming Cao wrote: > > On Sat, 2003-06-14 at 01:01, Andrew Morton wrote: > > > Was elevator=deadline observed to fail in earlier kernels? If not then it > > may be an anticipatory scheduler bug. It certainly had all the appearances > > of that. > Yes, with elevator=deadline the many fsx tests failed on 2.5.70-mm5. > > > So once you're really sure that elevator=deadline isn't going to fail, > > could you please test elevator=as? > > > Ok, the deadline test was run for 10 hours then I stopped it (for the > elevator=as test). > > But the test on elevator=as (2.5.70-mm9 kernel) still failed, same > problem. Some fsx tests are sleeping on io_schedule(). > > Next I think I will re-run test on elevator=deadline for 24 hours, to > make sure the problem is really gone there. After that maybe try a > different Qlogic Driver, currently I am using the driver from Qlogic > company(QLA2XXX V8). Martin has just observed what appears to be the same failure on 2.5.71-mjb1, which is the deadline scheduler, using qlogicisp. Again, some IO appears to have been submitted but it never came back. It could be a bug in the requests queueing code somewhere, or in the device driver. So a good thing to do now would be to find the workload+IO scheduler+filesystem which triggers it most easily, and run that with a different device driver. The feral driver (drivers/scsi/isp/ in -mm) should be suitable for that test. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org