On Monday 02 August 2010, 23:38:05 Rafael J. Wysocki wrote: > On Monday, August 02, 2010, Stephan Diestelhorst wrote: > > On Wednesday 28 July 2010, 23:50:09 Rafael J. Wysocki wrote: > > > On Saturday, July 10, 2010, Tejun Heo wrote: > > > > On 07/10/2010 08:50 AM, Stephan Diestelhorst wrote: > > > > >> I have a box where this problem is kind of reproducible, but it happens _very_ > > > > >> rarely. Also I can't reproduce it on demand running suspend-resume in a tight > > > > >> loop. Are you able to reproduce it more regurarly? > > > > > > > > > > For me it is much more reproducible. If I run multiple direct writing > > > > > dd-s to the disk in question I trigger it rather reliably (~75% or > > > > > higher). See the attached script from an earlier email. > > > > > Maybe that helps triggering your case more reliabl, too? > > > > > > > That didn't help, but the appended patch fixes the problem for me. > > > > <snip> > > > > Sorry for taking ages. Vacation and catching up after it are to blame, > > as is me forgetting to build a proper initrd... > > > > Thanks for the patch! It certainly changes behaviour, however, in a > > very strange way for me. With your patch my machine does not suspend > > to ram anymore (a simple echo mem > /proc/sys/state blocks), and > > nothing happens in dmesg if there is a lot of write I/O while > > suspending. (A number of parallel dd's with oflag=direct) > > > > If I stop the I/O, the system eventually goes into suspend to RAM. > > However, that takes a while, after the I/O has stopped, and also > > from "Preparing system for suspend" log entry until it is actually > > done. > > > > Is this intentional? > > It surely isn't. > > > Let me know how I can debug this further! > > Ideally I'd like to be able to suspend the machine under I/O load, > > too. (E.g. during a compile job.) > > > > Can you reproduce this at your end, too? > > Well, I didn't try suspending with a number of parallel dd's with oflag=direct > in the background, but otherwise I'm not reproducing the issue with > the patch applied. Mhmhm, I have tried to reproduce my issue again, and also added some dev_printk's around your code to understand where the delay is happening. However, I have not been able to reproduce the issue (with and without the debug output) anymore, and I am happy to report that for now your patch helps. I'd like to keep this under observation for a little while longer, though. Many thanks, Stephan -- Stephan Diestelhorst, AMD Operating System Research Center stephan.diestelhorst@xxxxxxx, Tel. +49 (0)351 448 356 719 Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach General Managers: Alberto Bozzo, Andrew Bowd Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632 _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
