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Re: Measurement of CPU usage
de Jast 05/07/2006 09:57
PaulFXH wrote:
> 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
Ok
Personally I would be more inclined to trust process explorer. Does the
task manager in win98 show a graph like it does in winxp? If so just
compare this graph against all the other ones.
>>> 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
>