Re: SMP/cc Cluster description [was Linux/Pro]

Rob Landley
2001-12-06T00:16:18Z

On Wednesday 05 December 2001 02:11 pm, Larry McVoy wrote:
> > If I give you 16 SMP systems, each with 4 processors and a gigabit
> > ethernet card, and connect those ethers through a switch, would that
> > be sufficient hardware?
>
> You've completely misunderstood the message, sorry, I must not have been
> clear. What I am proposing is to cluster *OS* images on a *single* SMP as a
> way of avoiding most of the locks necessary to scale up a single OS image
> on the same number of CPUs.
>
> It has nothing to do with clustering more than one system, it's not that
> kind of clustering. It's clustering OS images.

So basically, you're just turning the per-processor data into a tree?

> To make it easy, let's imagine you have a 16 way SMP box and an OS image
> that runs well on one CPU. Then a ccCluster would be 16 OS images, each
> running on a different CPU, all on the same hardware.
>
> DEC has done this, Sun has done this, IBM has really done this, but what
> none of them have done is make mmap() work across OS boundaries.

The shared memory clustering people are basically trying to make
mmap+semaphores work across a high speed LAN. Why? Because it's cheap, and
the programming model's familiar.

Approaching it all from a different direction, though. Probably not of help
to you...

Rob