Re: Scaling noise

David S. Miller
2003-09-04T04:49:59Z

On Wed, 3 Sep 2003 08:39:01 -0700
Larry McVoy <lm@bitmover.com> wrote:

> It's really easy to claim that scalability isn't the problem. Scaling
> changes in general cause very minute differences, it's just that there
> are a lot of them. There is constant pressure to scale further and people
> think it's cool.

So why are people still going down this path?

I'll tell you why, because as SMP issues start to embark upon
the mainstream boxes people are going to find clever solutions
to most of the memory sharing issues that cause all the "lock
overhead".

Things like RCU are just the tip of the iceberg. And think Larry,
we didn't have stuff like RCU back when you were directly working
and watching people work on huge SMP systems.

I think it's instructive to look at hyperthreading from another
angle in this argument, that the cpu people invested billions of
dollars in work to turn memory latency into free cpu cycles.

Put that in your pipe and smoke it :-)