Re: Scaling noise

Larry McVoy
2003-09-03T15:39:16Z

On Wed, Sep 03, 2003 at 08:23:44AM -0700, Martin J. Bligh wrote:
> > I think LM advocates aiming single image scalability at or before the knee
> > of the CPU vs performance curve. Say thats 4 way, it means you should get
> > good performance on 8 ways while keeping top performance on 1 and 2 and 4
> > ways. (Sorry if I mis-represent your position).
>
> Splitting big machines into a cluster is not a solution. However, oddly
> enough I actually agree with Larry, with one major caveat ... you have to
> make it an SSI cluster (single system image) - that way it's transparent
> to users.

Err, when did I ever say it wasn't SSI? If you look at what I said it's
clearly SSI. Unified process, device, file, and memory namespaces.

I'm pretty sure people were so eager to argue with my lovely personality
that they never bothered to understand the architecture. It's _always_
been SSI. I have slides going back at least 4 years that state this:

http://www.bitmover.com/talks/smp-clusters
http://www.bitmover.com/talks/cliq

> Numbers would be cool ... particularly if people can refrain from the
> "it's worse, therefore it must be some scalability change that's at fault"
> insta-moron-leap-of-logic.

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. You can argue you all you want that scaling done right
isn't a problem but nobody has ever managed to do it right. I know it's
politically incorrect to say this group won't either but there is no
evidence that they will.

Instead of doggedly following the footsteps down a path that hasn't worked
before, why not do something cool? The CC stuff is a fun place to work,
it's the last paradigm shift that will ever happen in OS, it's a chance
for Linux to actually do something new. I harp all the time that open
source is a copying mechanism and you are playing right into my hands.
Make me wrong. Do something new. Don't like this design? OK, then come
up with a better design.
--
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Larry McVoy lm at bitmover.com http://www.bitmover.com/lm