Weird context-switching performance

[Milo Hyson]

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
> > 
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