Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754701AbYGLO4R (ORCPT ); Sat, 12 Jul 2008 10:56:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753346AbYGLO4G (ORCPT ); Sat, 12 Jul 2008 10:56:06 -0400 Received: from casper.infradead.org ([85.118.1.10]:57579 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753330AbYGLO4F convert rfc822-to-8bit (ORCPT ); Sat, 12 Jul 2008 10:56:05 -0400 Date: Sat, 12 Jul 2008 07:55:32 -0700 From: Arjan van de Ven To: =?UTF-8?B?VMO2csO2aw==?= Edwin Cc: Linus Torvalds , Ingo Molnar , Roland McGrath , Thomas Gleixner , Andrew Morton , Linux Kernel Mailing List , Elias Oltmanns , Oleg Nesterov Subject: Re: [PATCH] x86_64: fix delayed signals Message-ID: <20080712075532.13483b21@infradead.org> In-Reply-To: <4878B4B5.5060007@gmail.com> References: <20080710215039.2A143154218@magilla.localdomain> <20080711054605.GA17851@elte.hu> <4878883F.10004@gmail.com> <4878B4B5.5060007@gmail.com> Organization: Intel X-Mailer: Claws Mail 3.5.0 (GTK+ 2.12.11; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1770 Lines: 42 On Sat, 12 Jul 2008 16:42:13 +0300 Török Edwin wrote: > On 2008-07-12 13:32, Török Edwin wrote: > > I haven't yet tried ftrace on this box, and neither did I try > > Roland's patch yet. I will try that now, and hopefuly come back > > with some numbers shortly. > > > > tip/master of today already includes Roland's patch, so I have tested > it without even knowing on the 64-bit box. > [After gathering all the traces, I wanted to repeat everything with > the patch applied, but there was no need since its already there]. > I can say that I didn't notice any difference in the delays (I still > get 24 - 30 second delays). > I also tried Linus's readdir patch, the latency is around 27 seconds > (was 30 before). I am not sure if it is an improvement, or measurement > noise. > > Also I wasn't able to reproduce the 'Ctrl+Z works faster than Ctrl+C' > symptom, perhaps it is just a coincidence: by the time I press Ctrl+Z > to interrupt, enough time has passed (30+ secs), that the same effect > would have been obtained by another Ctrl+C, or by just waiting. > > On 32-bit, I think the 2-3 seconds latency can be attributed to I/O > delays, and I think its acceptable given the slow disk (5k4 rpm sata). I see really bad delays on 32 bit as well, but they go away for me if I do echo 4096 > /sys/block/sda/queue/nr_requests -- If you want to reach me at my work email, use arjan@linux.intel.com For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/