Re: SMP/cc Cluster description

Larry McVoy
2001-12-06T22:37:53Z

On Thu, Dec 06, 2001 at 10:37:18PM +0000, Alan Cox wrote:
> > problem. Scheduler, networking, device drivers, everything. That's
> > thousands of locks and uncountable bugs, not to mention the impact on
> > uniprocessor performance.
>
> Most of my block drivers in Linux have one lock. The block queuing layer
> has one lock which is often the same lock.

Hooray! That's great and that's the way I'd like to keep it. Do you think
you can do that on a 64 way SMP? Not much chance, right?

> > You tell me - which is easier, multithreading the networking stack to
> > 64 way SMP or running 64 distinct networking stacks?
>
> Which is easier. Managing 64 routers or managing 1 router ?

That's a red herring, there are not 64 routers in either picture, there
are 64 ethernet interfaces in both pictures. So let me rephrase the
question: given 64 ethernets, 64 CPUs, on one machine, what's easier,
1 multithreaded networking stack or 64 independent networking stacks?
--
---
Larry McVoy lm at bitmover.com http://www.bitmover.com/lm