[ltp] Reliable Suspend/Resume (Was:Filesystem choice?)

[D. Sen]

Sometimes its the hardware.

I have a T30 that would stay up a maximum of three days. My usual mode 
of operation is about 3 suspend/resume cycles per day (before and after 
work and before the end of my working day at home).

But that was before the thinkpad went back to IBM *twice* for unrelated 
repairs (once because the battery wasnt being recharged and the second 
due to the second memory bank not working - both times requiring a 
motherboard swap). After the second system board replacement, the 
machine has been going through the suspend/resume cycle absolutely 
reliably. There has been *no* change in the software setup or BIOS. The 
only change has been that I now use "redisafe" (set in the BIOS) when 
suspending which takes slightly longer but if it means a reliable 
resume/suspend cycle...its MORE than worth it.

DS

Michael Selway wrote:
> Tilmann Singer writes:
>  > * Richard <rn214@hermes.cam.ac.uk> [20021106 12:21]:
>  > > My A22p used to fail about once per month to resume. It now fails about 1
>  > > time in 3 (It seems that the HDD doesn't spin up). So I don't let it
>  > > suspend anymore - I just turn off the screen (fn-F3) at night.
>  > 
>  > Sounds like the errors I've seen on my A20p after upgrading the kernel
>  > to 2.4.19. I remember reading somewhere that this is a known error in
>  > that kernel, went back to 2.4.18 and everything was fine again.
> 
> When I upgraded from redhat 7.2 (2.4.not-much) to redhat 7.3
> (2.4.18), the crash-on-resume problem got much much worse, like 1
> time in 2 failures or so.  Ironically, I'd only upgraded in the
> hope of fixing the occasional crashes.  I aleviated the problem
> back down to one-or-two crashes per month by shutting down my
> permanently-inserted pcmcia modem card before suspending (by using
> the apmd/apm-proxy stuff in redhat).  I've tried adding all sorts
> of exclusions to the pcmcia config file, but to no effect.
> 
> Indeed, I don't use any pcmcia cards now, and I still get the
> occasional crashes.
> 
> I agree with Richard that it seems like the problem is that the
> hdd doesn't spin up.  I played with reseting the IDE bus using an
> obscure ioctl() call, but that crashed the machine even more
> reliably(!).  I wondered if use of the CD/DVD drive was related,
> but I've had crashes when the drive has not been used since the
> last reboot.  I share richard's thoughts about using alt-sysrq to
> get the ide driver to reset things.  Maybe I should take a look at
> this if I can find some time.
> 
> I tried setting the APM_ALLOW_INTS kernel parameter to
> no-allow-ints.  It's a "well known fact" that thinkpads don't work
> with this setting, so well-known that there's code in
> arch/i386/kernel/dmi_scan.c which forces allow-ints if you're on a
> thinkpad.  I modified this code to allow me to play with the
> parameter, and for a while I thought I'd got it.  But I now
> believe this parameter setting makes no difference to my machine
> at all.
> 
> My latest stab is to turn off interrupts and dma from the disc at
> suspend time, as suggested again by the redhat /etc/sysconfig/apmd
> stuff.  I've been up for an inconclusive 6 days so far...
> 
> I have a long-held theory the problems might be related to NFS,
> but I don't have much evidence for this.  I use NFS a lot so it's
> harder to test this hypothesis.
> 
> Incidentally, I always shutdown using "apm --suspend", I wonder if
> that's an issue...?
> 
> Michael.

-- 
D. Sen, PhD
http://www.auditorymodels.org/~dsen