On 8/6/15 11:05 AM, Eric Christopherson wrote:
On Thu, Aug 6, 2015 at 12:41 PM, Guy Sotomayor <ggs
at shiresoft.com> wrote:
Back to the MP 3000. There are a number of CPUs
in the box. Two are the
most
obvious: the SBC running OS/2 and the actual S/390 CPU. However, there is
another
S/390 CPU in the box as well. It is not visible (at least directly) to S/W.
It is responsible
for providing the high performance I/O capabilities (like native disk access
and making
them appear as conventional channel attached devices instead of RAID-5 SSA
drives).
The OS/2 SBC is there to emulate some of the slower devices (card
reader/punch,
direct attached 3270s, etc).
So the OS/2 computer is actually a component of the
mainframe's
control processor, not a separate PC?
In various other S/390 and z/Series machines,
there is a laptop that is
the "service element" with
special S/W (now I think on Linux). On the MP3000, it is a single board
computer that is on what
looks like a big PCI card. By it's nature it is hooked into various
parts of the MP3000 system through
the various other things that sit on the PCI bus. Note that the PCI bus
is shared between the SBC
and the other parts of the MP3000.
If you don't fire up the system element software the OS/2 system would
appear as a somewhat
"normal" PC with a bunch of special device drivers.
There's a great diagram (too complicated to reproduce in ASCII art) that
illustrates all of the major
components in the MP3000. It's located in the IBM Redbook "Multiprise
3000 Technical Introduction".
It's Figure 1 on page 8 of the redbook. This is a really great
introduction on the MP3000.
TTFN - Guy