Re: vm lock contention reduction

Martin J. Bligh
2002-07-07T05:16:19Z

> I'd like to enhance the profiling support a bit, to create some
> infrastructure for doing different kinds of profiles, not just
> the current timer-based one (and not just for the kernel).
>
> There's also the P4 native support for "event buffers" or whatever intel
> calls them, that allows profiling at a lower level by interrupting not for
> every event, but only when the hw buffer overflows.

kernprof is capable of monitoring the CPU's stats gathering
counters I believe. The following is thanks to Mala Anand,
and I think she was monitoring the cacheline misses like this,
though the mechanism allows access to various things, I can't
remember if there's a TLB hit rate counter of the top of my
head ...

M.

-------------------------

The following script is what I used to collect performance counter
profiling data using kernprof:

sleep 5
kernprof -r -a 0xc0 -d pmc -f 1000 -t pc -b
sleep 30
kernprof -e -i -m /usr/src/linux/System.map > kpg.out
sort -nr +2 kpg.out > kpg26sort.out