Re: Linux & Multiple processing?

Kevin M Bealer (kmb203@psu.edu)
Sun, 9 Jun 1996 18:12:23 -0400 (EDT)


On Sat, 8 Jun 1996 pb90@columbia.edu wrote:

> I am wondering if the linux operating system takes advantage of computers
> with multiple processors!
> If yes would anyone know how many processors can Linux deal with at the
> same time?
>
> Any information welcome......Thank's

Look in the "smp" section in the kernel source, and there is some docs in
/usr/src/linux/Documentation...

I think the basic situation is thus: Kernels for multiprocessing have "fine
grained locking" or "coarse grained locking"... fine is better and coarse is
what is there now (I think)... it will eventually be fine grained.

By locking I believe they mean that since no two processes should be running
the same code at the same time, (or all the local variables get scrambled)
you need to make one CPU wait until the other is done with that part of the
code. The finer the grain, the more little chunks it is divided into.

The more little chunks, the less often it has to wait, the less performance
hit from multiprocessing. I don't know how much of a hit it is tho in
either case... I've never owned above a single-cpu 486-33.

__kmb203@psu.edu_________________________Debian__1.1___Linux__1.99.7___
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