20 Feb
2012
20 Feb
'12
11:24 p.m.
-----Original Message-----
From: cctalk-bounces at classiccmp.org
[mailto:cctalk-bounces at classiccmp.org] On Behalf Of Sean Conner
Sent: 20 February 2012 22:17
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: What is a mainframe? (was Re: NASA unplugs last
mainframe)
It was thus said that the Great Chuck Guzis once stated:
Serviceability",
At Newcastle there were lots of problems with their IBM 370 I think it was
eventually tracked down to some circuits with faulty bonding of the copper
to the pcbs in some units. Recently when we had an IBM MP3000 which some
would call a mainframe (It runs 370/xa and ESA code) it had a lower
availability that our Windows servers.
To me a Mainframe was largely about the i/o, so perhaps eparate, dedicated ,
programmable, identifiable i/o processor? I am note sure if the z9 has
these, or if like the MP3000 the i/o processors are "emulated" by a service
processor...
On 20 Feb 2012 at 10:43, William Donzelli wrote:
> > Can anyone fill in the ??? is an absolute and lucid
way, such that
> > any box, regardless of appearance must
pass the test in
question to
> > qualify as a "mainframe"?
> >
>
> Fill in the first question mark with an "R". Fill the
middle one
with
an
"A". Fill the last one with a "S".
If you're referencing "Reliability, Availability and I think that's not specific enough. ILLIAC
IV was certainly a
mainframe and had none of those.
Back in the late 90s I worked at a company that had
a
Stratus. If you
rebooted the machine, within twenty minutes, the Status
company would call
up asking if there were any issues we were experiencing and should a
technician be sent out?
There's also the apocraphyl story of a new fan unit showing
up at the
office---the Stratus noticed one of the existing fan units
was marginal and
had ordered itself a replacement.
So perhaps it is the service level that makes a mainframe a
mainframe.
-spc (The software the we wrote for the Stratus also ran
under Windows,
but cost significanly more ... )