From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751095AbWGKXAz (ORCPT ); Tue, 11 Jul 2006 19:00:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751183AbWGKXAz (ORCPT ); Tue, 11 Jul 2006 19:00:55 -0400 Received: from pop5-1.us4.outblaze.com ([205.158.62.125]:19414 "HELO pop5-1.us4.outblaze.com") by vger.kernel.org with SMTP id S1751095AbWGKXAy (ORCPT ); Tue, 11 Jul 2006 19:00:54 -0400 From: Nigel Cunningham To: "Rafael J. Wysocki" Subject: Re: uswsusp history lesson [was Re: [Suspend2-devel] Re: swsusp / suspend2 reliability] Date: Wed, 12 Jul 2006 09:00:45 +1000 User-Agent: KMail/1.9.1 Cc: Pavel Machek , suspend2-devel@lists.suspend2.net, Olivier Galibert , grundig , Avuton Olrich , jan@rychter.com, linux-kernel@vger.kernel.org References: <20060627133321.GB3019@elf.ucw.cz> <200607120801.24239.ncunningham@linuxmail.org> <200607120034.01339.rjw@sisk.pl> In-Reply-To: <200607120034.01339.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart1533929.uSSeH2680B"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200607120900.49828.ncunningham@linuxmail.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --nextPart1533929.uSSeH2680B Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Hi. On Wednesday 12 July 2006 08:34, Rafael J. Wysocki wrote: > On Wednesday 12 July 2006 00:01, Nigel Cunningham wrote: > > On Wednesday 12 July 2006 07:54, Rafael J. Wysocki wrote: > > > On Tuesday 11 July 2006 14:45, Nigel Cunningham wrote: > > > > Was that 10% speedup on suspend or resume, or both? With LZF, I see > > > > approximately double the speed with both reading and writing: > > > > > > I was not referring to the speedup of writing and/or reading. > > > > > > The exercise was to measure the time needed to suspend the system and > > > get it back in a responsive state. I measured the time elapsed betwe= en > > > triggering the suspend and the moment at which I could switch between > > > some applications in X without any noticeable lag due to faulting in > > > some pages (that is a bit subjective, I must admit, but I was willing > > > to show that bigger images make substantial difference). > > > > > > I tested uswsusp with compression (LZF) and two image sizes: 120 MB a= nd > > > (IIRC) about 220 MB on a 256 MB box. The result of the measurement f= or > > > the 120 MB image has always been greater than for the 220 MB image, b= ut > > > the difference has never been greater than 10%. > > > > Ah ok. Are you sure you're getting that sort of throughput with LZF > > though - if you're not, you might be underestimating the advantage. > > Certainly I don't get that kind of speedup for writing. For reading I do. Hmm. I would have expected it to be the other way round, since I guess you= =20 need to do the reading synchronously - or do you read the image, then=20 decompress it? (I'm reading and decompressing at the same time, using=20 readahead to avoid waiting for pages all the time). I haven't had the chance to revisit uswsusp yet - I did sysfs support on=20 Monday (took ages to figure it out!). Ah... so many things to do, and so=20 little time to do them all! Regards, Nigel =2D-=20 Nigel, Michelle and Alisdair Cunningham 5 Mitchell Street Cobden 3266 Victoria, Australia --nextPart1533929.uSSeH2680B Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) iD8DBQBEtC2hN0y+n1M3mo0RAs3cAJ0f0wIcyaBDsJfAavwqZ75mFTbeWQCcCEN3 L/mT+F4/D5G2ipwwpVKFLFk= =nmeo -----END PGP SIGNATURE----- --nextPart1533929.uSSeH2680B--