[mpich-discuss] Why is my quad core slower than cluster

[Scott Atchley]

On Jul 8, 2008, at 12:35 PM, zach wrote:

> I am using a cluster.
> Each pc has two cpus and they are Xeon. Each cpu has 4GB, i think red
> hat is running.
>
> I also use a pc at home- quad core intel chip, 8gb ram, ubuntu.
>
> Both are using mpich.
>
> I have found that my home pc is only running about 1/3 the speed of
> the cluster, and the number of processes (4) and code is the same.
>
> Can anyone tell me if this is typical, and why, or am I not optimizing
> something properly?
>
> Thanks
> Zach

Which processor (Harpertown?). Which kernel?

Kernels <= 2.6.20 use the wrong memory copy routine for Intel Core2  
cpus. Since all of your communication will use memory copy, it will  
make a difference.

Scott