From mboxrd@z Thu Jan 1 00:00:00 1970 From: Willi Mann Subject: Re: kernel 2.6.32 much slower than 2.6.31 on s2disk Date: Mon, 28 Dec 2009 09:25:45 +0100 Message-ID: <4B386B89.6000506@wm1.at> References: <200912272156.27174.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200912272156.27174.rjw@sisk.pl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: "Rafael J. Wysocki" Cc: linux-pm@lists.linux-foundation.org, linux-pm@lists.osdl.org List-Id: linux-pm@vger.kernel.org >> I don't know to how to do a reliable benchmark on this problem, espially as >> the required time probably very much depends on the exact state of the >> frozen system. Is there any change in 2.6.32 that might cause less memory to >> be stored on the suspend device, and thus require more random disk access >> after the restore? > > Actaully, yes, there is. > > Please try to increase the value in /sys/power/image_size to approximately > 1/2 of your RAM and report back (the number is in bytes). Without changing the image_size, it especially got much better when I downgraded QT 4.6 to QT 4.5 which does not work well with KDE 4.3 (seems to cause memleaks). However, image_size is already set to your recommended value (well, approximately): # cat /sys/power/image_size 951431086 My RAM size is 2 GB (however, I have intel graohics with shared mem, so some part is reserved), my swap size is a little bit more than 2 GB. I don't know what value image_size was set to when I tried first. Note that when I reported the issue first I used Debian kernel 2.6.32-1, (probably plain 2.6.32), while I'm now using Debian kernel 2.6.32-2 (according to the changelog 2.6.32.1) WM