SMP/dual (multi) core phase II

[dsr at tao.merseine.nu (Dan Ritter)]

On Sun, May 06, 2007 at 07:12:00PM -0400, markw at mohawksoft.com wrote:
> If someone has an educated argument against this position I would really
> like to be educated.

We have a easily parallelizable, highly math-intensive workload
that forms the core of our services. (We == work, that is.)
We start as many processes as we have CPU cores available as
determined by Linux. This scales linearly on both single-core
CPUs and multicore CPUs. It scales almost, but not quite,
linearly on HyperThreading CPUs.

> Second, does anyone out there know if dual core processors can (as a
> matter of hardware and OS implementation) be used to run two different
> processes simultaneously rather than merely two different threads of a
> single process. 

Yes.

> VMM map have to be loaded into the memory controller, meaning that
> separate processes with different virtual memory mapping could not benefit
> from two cores.

That is not the case. CPU cache is split between the processes,
but unless you have a program structure where the main loops
don't fit into cache, you are unlikely to see much impact.
Remember, you're running a multitasking OS anyway. Right?

-dsr-

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