Re: Largest installed, single, i 595?

["Steve Richter" <stephenrichter@xxxxxxxxx>]

On Thu, Dec 11, 2008 at 7:33 PM, CRPence <CRPbottle@xxxxxxxxx> wrote:
> McKown, John wrote:
> >  <<SNIP>>  The Power6 processor is much more powerful than
> > the CPU in the z. And the 595, if I'm reading correctly can
> > have 64 of them. The largest z maxes out at 32 processors
> > in a single box.
>
>   Without a special PTF, a single partition of i5/OS runs on a maximum
> of 32 processors.  I am not sure of the limitations of that expansion
> with regard to always-on, CUoD, or backup for failed; perhaps the PTF
> explains what it enables, although I doubt it.
>
>   I do not recall any similarly low limitation on z, which enables a
> variety of additional co-processors, I/O processors, and "specialty
> engines" as well.  Since z offers at least 64 CPU systems, any 32 CPU
> limit would seem likely to be a partition limit for an OS, similar to
> for i5/OS.

interested to know if the 32 CPU limit has to do with the "dispatcher
lock" discussed in this video ( at the 1:50 mark )
http://channel9.msdn.com/shows/Going+Deep/Mark-Russinovich-Inside-Windows-7/

the speaker says that up until windows 7, windows used CPU word sized
bitmaps to represent the state of each processor in the system.