how many processes is better?

Matthew Knepley knepley at
Thu Oct 26 07:53:16 CDT 2006

On 10/26/06, Yixun Liu <yxliu at> wrote:
>  Hi,
> I want to know how many processes is better. My computer is dual
> processors PC with superthread. According to the exampe ex2 I set the
> problem domain to 800*200. I set the number of processes to 1,2,4,10
> respecively and the runtime is 26, 19, 18, 15 respectively. How many
> processes is better. In my opinion 4(2processors * 2superthreads) is better
> based on my computer, but why 10 ran more quickly?

Again, this question is about gneric theory of parallel processing, and
really has not answer
as you pose it. I suggest the book "Parallel Computing" by Grama, et. al.


> Yixun

"Failure has a thousand explanations. Success doesn't need one" -- Sir Alec
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