2009/5/7 Nigel Cunningham <ncunningham@xxxxxxxxxxx>: > Hi. > > On Thu, 2009-05-07 at 16:49 -0700, Arve Hjønnevåg wrote: >> On Thu, May 7, 2009 at 3:41 AM, Pavel Machek <pavel@xxxxxx> wrote: >> > If the code runs for 20 seconds, it is a bug to be fixed. >> >> The code gives up after 20 seconds, it does not normally run for 20 >> seconds. It is arguably a bug that it gives up after 20 seconds since >> the time required to freeze all the threads grows with the number of >> threads that are running. It could still be making progress after 20 >> seconds. Since the time required to freeze all tasks is the number of >> tasks times the time it takes to interrupt each task there is no way >> to ensure that the time required is insignificant. If we do not abort >> task freezing when there is a wakeup event, then the worst case wakeup >> latency is guarantied to be worse than the worst case latency for any >> other uninterruptible kernel call. > > I agree with Pavel here. If freezing takes 20 seconds, something is > wrong. (Remember that most tasks will not be running, and will therefore > respond to the pseudo-signal and freeze immediately). > > In fact, I'd go further. In the thousands of times I've run the freezer > over the years, it has never taken more than 1 second - let alone 20 - One second is to long. > when freezing has been successful. A delay of 20 seconds was more > relevant when the value included the time for syncing data to disk. This patch does nothing with the 20 second timeout. -- Arve Hjønnevåg _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
