Processor Time Allocation

G

Guest

Guest
Archived from groups: microsoft.public.windowsxp.general (More info?)

Does anyone know if there is a maximum processor percentage that Windows XP
allocates to a single program in a dual processor system?

I have a dual processor AMD Opteron, 4 gig of memory and a 2-200Gig SATA Raid
0 hard drive setup. I have noticed that the operating system will not allow
any one program to have more than 50% of the processor time. I have several
large computer models and when they are running, they use both processors
with each thread getting avriable usage percentage, but the total as reported
by Task Manager/Performance is always pegged at 50%. Not 49% and not 51%.

When I am running multiple programs I can get the total processor usage to
go over 50%, but for any one program that can get there, something is
stopping it from getting more than 50% of the combined available processor
time.

I have noticed this with several high end computer model as well as some code
that I developed myself and compiled at multithreaded. To reduce runtime I
would like to be able to allocate 100% of both processors if the program
needs it.
 
G

Guest

Guest
Archived from groups: microsoft.public.windowsxp.general (More info?)

Hydrology wrote:
> Does anyone know if there is a maximum processor percentage that Windows XP
> allocates to a single program in a dual processor system?
>
> I have a dual processor AMD Opteron, 4 gig of memory and a 2-200Gig SATA Raid
> 0 hard drive setup. I have noticed that the operating system will not allow
> any one program to have more than 50% of the processor time. I have several
> large computer models and when they are running, they use both processors
> with each thread getting avriable usage percentage, but the total as reported
> by Task Manager/Performance is always pegged at 50%. Not 49% and not 51%.
>
> When I am running multiple programs I can get the total processor usage to
> go over 50%, but for any one program that can get there, something is
> stopping it from getting more than 50% of the combined available processor
> time.
>
> I have noticed this with several high end computer model as well as some code
> that I developed myself and compiled at multithreaded. To reduce runtime I
> would like to be able to allocate 100% of both processors if the program
> needs it.

To do this the program needs to be written in such a way that it knows
how to take advantage of multiple processors. Simply being
multi-threaded is not enough. The vast majority of programs are not
written to be multi-processor capable.
--
Tom Porterfield
MS-MVP Windows
http://support.telop.org

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