Multiple CPUS versus one fast CPU

[John Thompson]

On 2008-02-07, Leslie Satenstein <lsatenstein at yahoo.com> wrote:

> There is a Queuing theory conclusion that   one cpu at speed 2x is better=
>  than two cpus at speed x.
>
> The reason is that it takes overhead to schedule two and also each cpu ca=
> n interfere with the other through locks, or memory access.
>
> But to reduce power consumption today, the trend is to 2 cpus at speed x.=
>  Increasing the speed causes a disproportionate increase in power consump=
> tion. The two cpu solution generally uses less power.
>
> What is the difference expected in performance? 

I think it would depend on what sort of processes are running. For 
interrupt-dependent processes, have two cpus doubles the available 
interrupts.

-- 

John (john at os2.dhs.org)