Re: Weird context-switching performance
From: Milo Hyson (milo_at_cyberlifelabs.com)
To: Julian Elischer <email@example.com> Date: Sat, 31 Jan 2004 18:00:39 -0800
We don't have any other systems that are as similar as the two in the
test, however we did plot context-switching performance against CPU and
memory performance on several systems to see if anything jumped out. We
found that beastie (the 2200+) is doing only about 26% of the
task-switches/dhrystone that the other systems were, which were all
pretty much about equal with each other. This is consistent with the
observation that appserver (the 2100+) is four-times as fast. I think we
can probably conclude that beastie is running slower than it should.
So the question still remains. What could affect context-switching to
this degree yet not show up in other benchmarks?
-- Milo Hyson Chief "Mad" Scientist CyberLife Labs, LLC On Sat, 2004-01-31 at 15:35, Julian Elischer wrote: > On Sat, 31 Jan 2004, Milo Hyson wrote: > > > We've got these two very similar machines that are exhibiting > > drastically different context-switching performance. The slower of the > > two is actually task-switching at four times the rate of the other. > > We've gone through several benchmarks and are at a complete loss to > > explain it. We've set up a page documenting our efforts: > > > > http://www.cyberlifelabs.com/cs-benchmark/ > > > > I would appreciate it if someone could offer some insight into what > > affects context-switching. Is there some obscure kernel variable that > > we've overlooked? Or is it just one of those unexplainable feng-shui > > situations? > > > > Which is the abnormal machine? > i.e. is machine 1 faster than all other similar machines or is machine B > slower? > > > > > Thanks in advance. > > > > -- > > Milo Hyson > > Chief "Mad" Scientist > > CyberLife Labs, LLC > > > > _______________________________________________ > > firstname.lastname@example.org mailing list > > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > > To unsubscribe, send any mail to "email@example.com" > > _______________________________________________ firstname.lastname@example.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "email@example.com"