Subject: Re: Processes getting stuck in disk wait on current currents
To: Mark Davies <mark@MCS.VUW.AC.NZ>
From: Wayne Knowles <>
List: current-users
Date: 02/18/2001 18:41:01
On Sun, 18 Feb 2001, Mark Davies wrote:

> 	From:  Wayne Knowles <>
> 	Date:  Sat, 17 Feb 2001 23:30:49 +1300 (NZDT)
> > My next step is to try and get closer to the date the problem was
> > introduced - unfortunately that can be a time consuming process!
> I think I mentioned this in my original post, if not...
> I don't see the problem in a Feb 4 build and do in Feb 9.

Hi Mark,

I have narrowed it down a little closer.  Kernels after Feb 5th have the
problem.  From what I can tell it was introduced with rev 1.90 of
sys/uvm/uvm_map.c as I can backout that patch on a Feb 5th kernel and the
problem goes away.

Also with DEBUG and DIAGNOSTIC enabled in the kernel I get the following
error several minutes before the freeze:

  vn_flush: oor vp 0x81c84580 start 0x0 stop 0x100e4000 size 0x1000

Next step is to update the kernel back to -current and back out the
suspected patch.  Will try and get a stack traceback at the time of the
vn_flush error which may be helpful to the VM folk.  Will also record
UVMHIST information.   Hope to have some more info in a few hours.

  _____	   	Wayne Knowles,  Systems Manager
 / o   \/   	National Institute of Water & Atmospheric Research Ltd
 \/  v /\   	P.O. Box 14-901 Kilbirnie, Wellington, NEW ZEALAND
  `---'     	Email: