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Re: Measurement of CPU usage
de PaulFXH 05/07/2006 04:12
Jast escreveu:
> PaulFXH wrote:
> > Hi
> > Not looking for FreeWare--just trying to hear some opinions on
> > something that been bothering me for some time.
> > I use WinMe as OS and have downloaded various small utilities (all
> > FREE) to view CPU Usage on my computer.
> > These included Process Explorer, ActiveCPU, FreeMeter and WinTop.
> > Trouble is, they don't all show the same result. Indeed, the CPU Usage
> > results seem to fall into one of two distinct categories; very high or
> > very low.
> > As an example, while writing this I have all four of the above
> > utilities running showing the CPU usage (note that I have only one
> > single-core processor on this box). So, while Process Explorer and
> > WinTop show about 3.5% usage, FreeMeter and ActiveCPU, on the other
> > hand, both show about 64%.
> > I have seen exactly the same thing on at least one other computer
> > (running on WinXP).
> > I have posted to a number of groups trying to get somebody to explain
> > why there is this large difference and what significance should be
> > attached to it. I have even e-mailed the author of one of the
> > utilities.
> > However, up to now, nobody seems able, or willing, to provide an
> > explanation.
> > Is there anybody out there who can point me in the right direction on
> > this one?
> > TIA
> > Paul
> >
Hi Jast
Thanks a lot for your reply.
See my comments below.
>
> I guess it depends on how you are testing them? You should have a
> standard load set up, say a big avi file or something that maxes out
> your cpu at around 50 to 90% then monitor this using only one of your
> CPU monitors.
The problem here, Jast, is that I already have an indication of CPU
Usage in the range suggested by you. Thus, FreeMeter and ACPU were
reading 64% (more or less) when I did the test. Interestingly, this was
WITHOUT anything very big running, certainly no AVIs.
> Then do the same thing with each one going. Running all of
> them at once will produce different results because they are sampling at
> different times and thus different results.
OK, but the difference that I mentioned in my first post was 3.5% Vs.
64%. That's very nearly a factor of 20. I don't think you need to be
mathematical genius to see that this is not due to different sampling
times.
> Also, try increasing the
> sample period or update speed to something bigger, say at least 2 to 5
> seconds as this may average over a longer time and thus give better,
> smoother more accurate results.
Actually, the sampling time, in those where it can be changed, is right
now 2 seconds. Even so, were the difference between the various results
4% Vs. 4.5%, I think we might be able to attribute it to a sampling
problem.
But 3.5% Vs. 64%, I thing we can safely rule out sampling as an
explanation for this astronomical difference.
Thanks again
Paul