Re: [PATCH] kprobes for s390 architecture

Mike Grundy
2006-07-11T13:54:11Z

On Fri, Jul 07, 2006 at 07:25:55PM +0200, Heiko Carstens wrote:
> > ok, I tried, but my "better ideas" made things worse. stop_machine_run() wins:
> How fast is this if you have to exchange several hundred instructions?

I did a little measuring. On average stop_machine_run() adds 8.7 msec of
overhead on a 4-way config. Of that %57 was sub-msec overhead. For the times
where overhead was measurable, the average was 20.2 msec, lowest at 10msec
highest at 100msec. That's on a z800 under vm and I have no idea how many real
cpus the machine has :-)

--
Thanks
Mike

=========================================
Michael Grundy - grundym@us.ibm.com
Advanced Linux Response Team (ALRT)
http://ltc.linux.ibm.com/teamweb/alrt/
845-435-8842 (T/L 295)

If at first you don't succeed, call in an air strike.