Re: Scaling noise

Mike Fedyk
2003-09-04T02:41:40Z

On Wed, Sep 03, 2003 at 07:31:13PM -0700, Martin J. Bligh wrote:
> > Unfortunately, this means
> > (a) the box needs a hypervisor (or equivalent in native nomenclature)
> > (b) substantial outlay of kernel hacking time (who's doing this?)
> >
> > I'm vaguely attached to the idea of there being _something_ to assess,
> > otherwise it's difficult to ground the discussions in evidence, though
> > worse comes to worse, we can break down to plotting and scheming again.
>
> I don't think the initial development baby-steps are *too* bad, and don't
> even have to be done on a NUMA box - a pair of PCs connected by 100baseT
> would work. Personally, I think the first step is to do task migration -
> migrate a process without it realising from one linux instance to another.
> Start without the more complex bits like shared filehandles, etc. Something
> that just writes 1,2,3,4 to a file. It could even just use shared root NFS,
> I think that works already.
>
> Basically swap it out on one node, and in on another, though obviously
> there's more state to take across than just RAM. I was talking to Tridge
> the other day, and he said someone had hacked up something in userspace
> which kinda worked ... I'll get some details.
>
> I view UP -> SMP -> NUMA -> SSI on NUMA -> SSI on many PCs -> beowulf cluster
> as a continuum ... the SSI problems are easier on NUMA, because you can
> wimp out on things like shmem much easier, but it's all similar.

Am I missing something, but why hasn't openmosix been brought into this
discussion? It looks like the perfect base for something like this. All
that it needs is some cleanup.