Re: 2.4.20: Proccess stuck in __lock_page ...

[Con Kolivas <kernel@kolivas.org>]

On Wed, 28 May 2003 23:08, Jens Axboe wrote:
> On Wed, May 28 2003, Carl-Daniel Hailfinger wrote:
> > Jens Axboe wrote:
> > > On Wed, May 28 2003, Marc-Christian Petersen wrote:
> > >>On Wednesday 28 May 2003 13:27, Andrew Morton wrote:
> > >>>Guys, you're the ones who can reproduce this.  Please spend more time
> > >>>working out which chunk (or combination thereof) actually fixes the
> > >>>problem.  If indeed any of them do.
> > >>
> > >>As I said, I will test it this evening. ATM I don't have time to
> > >>recompile and reboot. This evening I will test extensively, even on
> > >>SMP, SCSI, IDE and so on.
> > >
> > > May I ask how you are reproducing the bad results? I'm trying in vain
> > > here...
> >
> > Quoting Con Kolivas:
> >
> > dd if=/dev/zero of=dump bs=4096 count=512000
>
> already tried that, no go. on ide/scsi? what filesystem? how much ram?
> anything else running? smp/up?

I'm using UP on IDE. I reproduce it easily on a P3 256Mb laptop with 5400rpm 
drive, and less easily but still occurs on a P4 2.53 512Mb pc with 2x7200rpm 
software raid 0 IDE drives. Even if the only thing you try to do is move the 
mouse, the mouse will freeze for up to 30secs. When you first start the write 
no disk activity happens for up to a few seconds, then it will start writing 
madly and the machine will come to a standstill for a variable length of 
time. Then it will come back to life for a few seconds only to die again for 
a few seconds and so on till the write is complete.

Still testing combinations to see which is the best, but 1+2 seems better than 
3 alone as doing reads midstream in the write don't cause hangs. I haven't 
seen zombie processes ever.

Con