Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763119AbZLQUgC (ORCPT ); Thu, 17 Dec 2009 15:36:02 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762781AbZLQUf6 (ORCPT ); Thu, 17 Dec 2009 15:35:58 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:35491 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759915AbZLQUf5 (ORCPT ); Thu, 17 Dec 2009 15:35:57 -0500 From: "Rafael J. Wysocki" To: Alan Stern Subject: Re: Async suspend-resume patch w/ completions (was: Re: Async suspend-resume patch w/ rwsems) Date: Thu, 17 Dec 2009 21:36:36 +0100 User-Agent: KMail/1.12.3 (Linux/2.6.32-rjw; KDE/4.3.3; x86_64; ; ) Cc: Linus Torvalds , Zhang Rui , LKML , ACPI Devel Maling List , pm list References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200912172136.36277.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1744 Lines: 46 On Thursday 17 December 2009, Alan Stern wrote: > On Thu, 17 Dec 2009, Rafael J. Wysocki wrote: > > > That actually is correct. On the nx6325 suspend is totally dominated by disk > > spindown, almost everything else is negligible compared to it (well, except for > > the audio), so we can't go down below 1 s during suspend on this box. > > > > On the Wind, disk spindown time is comparable with serio suspend time, > > so at least in principle we should be able to get .5 s suspend on this box - > > if the disk spindown in async. > > > > In turn, the resume on the Wind is dominated by disk spinup, so we can't > > go below 1.5 s on this box during resume (notice that the "async+extra" > > approach brings us close to this limit, although we could save .5 s more in > > principle by making more devices async). > > > > Resume on the nx6325 is a different story, though, as it is dominated by USB > > and PCI devices, so marking those as async would probably bring us close to > > the limit. > > The implications seem pretty clear. If the following sorts of devices > were async: > > USB (devices and interfaces), PCI, serio, SCSI (hosts, targets, > devices) Plus ACPI battery. > then we would reap close to the maximum benefit -- providing: > > async threads are started in a first pass without waiting > for synchronous devices, and Agreed. > It's not clear that making all these types of devices async will really > work, but it's worth testing. I'm working on it. Rafael -- 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/