6.1 responsiveness under heavy (cpu?) load + thread monitoring

[Mathieu Prevot]

Hello,

I have a RELENG_6/AMD64 with an AMD64X2 cpu, 1GB of memory, 512MB swap.
I remarked that when I run 2 simulation program [1], sometimes, one of them
run one or several of its threads [2] very slowly, but sometimes, it doesn't
occur.

I remarked that is doesn't depend on SMP/UP, ULE/4BSD, i386/AMD64.

It seems to occur also with the kernel stress test under the same conditions
(all of them).
In this case, the mouse is blocked, etc. I tested different kernels, and
recorded the output of sysctl vm [3].

I increased vm.swap_async_max but this doesn't change the deal /a priori/.

All that didn't occur with a Sempron64. All was slower but the mouse didn't
blocked etc. This was a time ago, I may be wrong.

It seems to be an architecture problem (??).
I can give more quantitative data, but I need help to focus the tests...

Mathieu

[1] http://ising.podzone.org/src/ising_lps_0.4.tar.bz2
[2] void *interface(void *arg) can be very slow, void *system_trace(void *arg)
 can exit during a very long time (terminated ? detached: it should).
[3] http://ising.podzone.org/vm/vm_amd64.tar.bz2 and others in this directory

PS: does FreeBSD allow monitoring threads of a program in real time ?
I didn't find anything for freebsd.