[Info-vax] Reimplementing VMS, was: Re: HP adds OpenVMS Mature Product Support beyond the end of Standard Support

[JF Mezei]

On 14-02-04 10:32, Stephen Hoffman wrote:

> While QPI definitely helps when you're scaling past one socket, VMS 
> already has support for NUMA box designs, and that'll be useful even 
> with QPI.

I was under the impression that NUMA support didn't make it to Itanium
version. I take it that the "common source" between Alpha and Itanium
means that the code is still there, but just #IFDEF out when compiled on
IA64 ?

For the sake of discussion, say an Alpha system were built with 4 chips
of 4cores each, and Quickpath memory. (Alpha never supported dual core,
so not sure if the Alpha version of VMS has multi core support)

In the Galaxy/Wildfire class machines, there were separate memory banks,
with a "slow" interconnect. So each CPU block had its own "near" memory.
So it made sense to have system management tools to load processes on
specific CPUs, allocate their memory on the "near" RAM, and install
shareable imaged on near RAM too.

But in the case of Quickpath modern implementations, aren't systems
built with multiple paths into one memory bank ?  or is it still a
design where each CPU chip would controls a part of total memory (which
would be "near" to it) and have to Quickpath via another chip to get to
"far" memory controlled by another ?