[ltp] Filesystem choice?

[Michael Selway]

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.