Re: VOP_PUTPAGE ignores mount_nfs -o soft,intr

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Sat, Jun 20, 2015 at 07:56:29PM -0500, Don Lee wrote:
> FWIW, I have had a problem with my server getting stuck in "tstile". I could not reproduce the problem easily, but I saw it in production often enough that it was a headache.  The Intel port (as opposed to PPC) seems not to have the problem.
> 
> If there is no timeout on this loop, and it theoretically only has a problem on HW errors, I have doubts. The machine with the hangs does not have any other symptoms of HW errors. HOWEVER, I have a persistent suspicion that the PPC port drops interrupts on occasion. Just sayin.
> 
> If this hang happens, I think a panic is far better than a hang. What I would see is the machine lock up hard, with zillions of processes "stuck" in tstile, and no new procs could start. If I caught this early, I could get a couple of ps outputs done. Otherwise, I could get into the kernel debugger - sometimes.

"tstile" is a generic wait channel used by cv_wait().
Any code using cv_wait() could end up stuck here, so your problem
may be completely unrelated to vnodes ... or even if it's related
to vnodes, is may be a different issue.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
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