resume slow on Thinkpad T42 FreeBSD 8-STABLE

[Ian Smith]

On Wed, 24 Feb 2010, Ted Faber wrote:

 > I'm running a recent (yesterday) FreeBSD 8-STABLE on my T42.  When I
 > resume from suspend the fan starts screen returns immediately (to text
 > mode) and then the system idles for about a minute until it shakes
 > itself awake.  The keyboard LEDs cycle, the disk runs and X returns.

Good to hear, Ted .. I thought it was just me :)  Your symptoms appear 
entirely identical to mine as posted on Dec 13th to mobile@ and acpi@, 
see thread 'Thinkpad T23 60 second stall on resuming 8.0-RELEASE/i386' 
http://lists.freebsd.org/pipermail/freebsd-acpi/2009-December/006192.html

Nate Lawson thought it an ATA rather than an ACPI problem and I assume 
he's likely right, but I've had too much $work (and too little solar 
power during an exceptionally wet summer) to follow it up.

 > I don't recall this stutter under FreeBSD 7.  I've tried both settings
 > of hw.acpi.reset_video and neither helps (nor hurts).  BIOS is also
 > upgraded to the most recent and the stutter occurred with before and
 > after the upgrade.

I'd recently upgraded t23's BIOS too.  Since then I took 7.0-RELEASE to 
7.2-STABLE (28 Dec) and still have no such issue on 7, although the ATA 
messages on resume are marginally different.  I haven't yet upgraded my
8.0-R to -STABLE; going by this it seems that's unlikely to help now.

In case relevant, my ad0 is a 120GB Fujitsu MHV2120AH, but your TOSHIBA 
MK4026GAX looks more likely to be the original disk?

 > I have attached a trace of a boot -v going through the cycle.  The
 > t_delta entries happen after the machine wakes but before it restores
 > itself.  There'a also sometimes a message from acpi_ec0 saying that the
 > EC woke up before the sleep event, but I wasn't able to capture it
 > during this trace.

In that post I mntioned some other symptoms regarding devd and "calcru: 
time went backwards .." messages, but I suspect those were side-effects.

Once it resumes after the one-minute delay I've noticed no other issues, 
but can't claim to have spent much time exercising it.

 > Any help would be appreciated, and I'm happy to provide more data on
 > request.

I've no time to spend on hunting this now, and know nothing about ATA 
anyway, assuming that's where the problem lies, but I'll be quick to 
test any suggested solution/s!

cheers, Ian