Wedging on low memory systems

[John Klos <john%ziaspace.com@localhost>]

Hello,

I have two low memory machines that wedge now and then, and so far I 
haven't had much luck getting in to the kernel debugger to see what's up 
when it happens.

One system is a Mac LC II with 10 megabytes. Even just trying to let it 
run the default startup startup scripts will result in a wedge, and I have 
never succeeded in getting to the kernel debugger on it.

The other is an LC III+ with 36 megs. This has been enough memory that 
I've been able to do things like compile Perl, but now and then it still 
wedges.

I did notice that this reduces the incidence of wedging:

vm.anonmax: 80 -> 60
vm.filemax: 50 -> 30
vm.filemin: 10 -> 5

Today it wedged while building stuff in pkgsrc, and although I was able to 
get in to the kernel debugger, it didn't respond to the keyboard. However, 
SIGINFO on an open shell gave:

[ 3462044.0029799] load: 0.00  cmd: sh 20540 [ptpage] 0.00u 0.00s 0% 0k

This makes me wonder if we're miscalculating nptpage and it shows up only 
on low memory systems. Thoughts or suggestions?

John