Re: Memory allocation problem with 2.6.22 after suspend/resume cycle

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Sunday, 23 September 2007 18:19, Christian P. Schmidt wrote:
> Rafael J. Wysocki wrote:
> > On Sunday, 23 September 2007 14:38, Christian P. Schmidt wrote:
> >> Rafael J. Wysocki wrote:
> >>> On Saturday, 22 September 2007 17:41, Christian P. Schmidt wrote:
> >>>> Hi all,
> >>>>
> >>>> I'm having a strange problem, of course not reproducible. Sometimes
> >>>> after a suspend (to ram) and resume cycle, the kernel will try to free
> >>>> all memory. This means, all running applications are flushed to swap (as
> >>>> long as it is available), caches and buffers stay at around 15MB each.
> >>>>
> >>>> The following video (traded quality for bandwidth) shows what happens on
> >>>> the way from no swap to "swapon -a" (that's the unreadable thing in the
> >>>> small shell): http://digadd.de/swapping.avi
> >>>>
> >>>> The system:
> >>>> Linux dnnote 2.6.22.5 #1 SMP PREEMPT Sat Aug 25 18:39:21 AST 2007 x86_64
> >>>> Intel(R) Core(TM)2 CPU T7400 @ 2.16GHz GenuineIntel GNU/Linux
> >>> Are you using an ATI binary graphics driver?
> >> Yes. I do not (yet) have a choice... can't wait for the open source drivers.
> > 
> > That, most probably, is the source of the problem.  Please see:
> > http://bugzilla.kernel.org/show_bug.cgi?id=8943
> 
> I do however not agree with Andrew's conclusion, as the memory is not
> "used", so I wouldn't expect a memory leak. As soon as I turn swapping
> off everything is loaded again, and works. If there was a leak it should
> use the memory, shouldn't it?
> If the problem would be 100% reproducible I could try without, but as
> is, I have up to two weeks with 2-3 cycles daily (sometimes more, as I
> receive untraceable SERR from my PCI-E WLAN after which I do not receive
> interrupts any more - only a suspend/resume cycle helps...) before the
> problem occurs.
> 
> Anyway, is there a way of unloading the module temporarily without
> shutting X down?

I don't know.

Can you try another version of the ATI driver?  The reporter of this bugzilla
entry did that and it apparently helped him:
http://bugzilla.kernel.org/show_bug.cgi?id=8943#c4

> >>>> A 32bit Kernel is unable to suspend/resume at all. No idea why. dmesg
> >>>> shows nothing, logs show nothing. Any ideas for debugging are welcome.
> >>> Well, that's interesting.
> >>>
> >>> Can you try in the minimal configuration (ie. boot with init=/bin/bash,
> >>> mount /sys, mount /proc and run "echo mem > /sys/power/disk)?
> >> Which? the 32bit or the 64bit?
> > 
> > 32-bit, but please do that without the ATI driver.
> 
> Did it. As before, suspends, but when I resume, I hear the CD-ROM spin
> up, the backlight comes on, and nothing more. The system is a Lenovo
> Thinkpad T60 8744-4XG, BIOS 1.09.

Are you 100% sure that your 32-bit kernel configuration reflects the 64-bit
one?  In particular, do you have CONFIG_NO_HZ set in the 32-bit .config?

Also, would you be able to repeat this test with the latest -git kernel
(currently 2.6.23-rc7-git4)?

Greetings,
Rafael