graphics on G4

[Justin Hibbits]

Hi Peter,

On Wed, Oct 22, 2008 at 01:57:14AM +1000, Peter Grehan wrote:
> Hi Justin,
> 
> >An oddity I've found with FreeBSD/ppc on my G4 MDD --
> >when I do anything with graphics, after a while the
> >whole machine just hangs when I try to spawn a new
> >process.  It's not a deterministic problem, it just
> >happens 'eventually', but nearly 100% of the time it
> >does happen
> 
>  The framebuffer uses a large chunk of kernel VM when mmap'd.
> Are you able to dump some vm stats while doing this e.g.
> sysctl vm.kvm_free ?
> 
> later,
> 
> Peter.

There is no vm.kvm_free sysctl on my install.  Here are the stats from sysctl
vm.phys_free, vm.vmtotal, and vm.loadavg while running X/windowmaker

vm.phys_free: 
FREE LIST 0:

  ORDER (SIZE)  |  NUMBER
                |  POOL 0  |  POOL 1  |  POOL 2
--            -- --      -- --      -- --      --
  10 (  4096K)  |       0  |       0  |       0
   9 (  2048K)  |       0  |       0  |       0
   8 (  1024K)  |       0  |       0  |       0
   7 (   512K)  |       0  |       0  |       0
   6 (   256K)  |       0  |       0  |       0
   5 (   128K)  |       0  |       0  |       0
   4 (    64K)  |       0  |       0  |       0
   3 (    32K)  |       0  |       0  |       0
   2 (    16K)  |       0  |       0  |       0
   1 (     8K)  |      57  |       0  |     605
   0 (     4K)  |       2  |      23  |   13370
 
vm.vmtotal: 
System wide totals computed every five seconds: (values in kilobytes)
===============================================
Processes:              (RUNQ: 1 Disk Wait: 0 Page Wait: 0 Sleep: 74)
Virtual Memory:         (Total: 1391388K, Active 288188K)
Real Memory:            (Total: 142548K Active 130496K)
Shared Virtual Memory:  (Total: 53356K Active: 51276K)
Shared Real Memory:     (Total: 23100K Active: 22912K)
Free Memory Pages:      58896K

vm.loadavg: { 0.15 0.10 0.07 }

What other stats are relevant?

I neglected to mention before, but it happens even when I exit out of X, or the
program mmap()ing the video card quits.  I have a hunch that it's overwriting
some piece of memory needed by the process list.

- Justin