Re: LOR's in VM

On 02 Jul 2004, Mark Nipper wrote:
> > lock order reversal
> >  1st 0xc0698ac0 UMA lock (UMA lock) _at_
> >  /usr/src/sys/vm/uma_core.c:1200
> >  2nd 0xc0c31100 system map (system map) _at_
> >  /usr/src/sys/vm/vm_map.c:2210
> > lock order reversal
> >  1st 0xc95b1bdc vm object (vm object) _at_
> >  /usr/src/sys/vm/swap_pager.c:1323
> >  2nd 0xc0697f60 swap_pager swhash (swap_pager swhash) _at_
> >  /usr/src/sys/vm/swap_pager.c:1838
> >  3rd 0xc0c38738 vm object (vm object) _at_
> >  /usr/src/sys/vm/uma_core.c:873

	Well, I hate to do it, but I found the LOR page (doh!),
and it looks like those are 007 and 001 respectively.  I was
hoping not though because I've had some hard freezes (power
button to recover) under heavy disk access, one being when a
large number of clients were hitting my Debian mirror on the
machine via HTTP (Apache 1.3.x) and the other being during heavy
disk access after such a crash while NFS clients were trying to
ramp back up and background fsck was happening simultaneously.

	Those situations only occurred though without all the
debugging options turned on in the kernel.  Now that I have them
turned on, it doesn't seem to happen anymore, the machine is just
slow as sin.  :)  Oh well, maybe I just need to move to the
latest 5.2.1 patch level.

-- 
Mark Nipper                                                e-contacts:
Computing and Information Services                      nipsy_at_tamu.edu
Texas A&M University                        http://ops.tamu.edu/nipsy/
College Station, TX 77843-3142     AIM/Yahoo: texasnipsy ICQ: 66971617
(979)575-3193                                      MSN: nipsy_at_tamu.edu

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