Phil,
Unless there was something else out there (a poster or whatever), that
would have been me doing a riff in my VM Performance classes, first for
Amdahl, then for Velocity. Your buddy's time frame is about right (15 years
ago). I was attempting to emphasize the impact of an RPS miss (show of
hands: who remembers what that was?) on response time.
The riff started by me "complaining" that I didn't have a good intuitive
grasp of how fast CPUs were (tens of nanosecond cycle times at that point),
so "let's slow down our timeframe and say a CPU cycle is one second. Then a
page fault from Xstore is satisfied in [nn minutes], a DASD I/O satisfied
from cache takes [mm hours] and one that has to go to the real disk takes
[kk days]. An RPS miss adds [I think it was 16 hours] to that."
Alas, a quick search of my notes didn't turn up a copy of the discussion,
so I can't fill in the blanks. Perhaps someone who took one of the classes
and wrote it down....
Marty
____________________
Martin Zimelis
Principal
maz/Consultancy
> -----Original Message-----
> From: The IBM z/VM Operating System
> [mailto:[EMAIL PROTECTED] On Behalf Of Phil Smith III
> Sent: Thursday, November 08, 2007 1:48 PM
> To: [email protected]
> Subject: Poster of computer hardware events?
>
> A buddy asked me:
>
> "At a previous employer, someone had an article, poster or
> something (I know - real specific - it was 15+ years ago)
> that tried to put the time for computer events into
> perspective. It started with the quickest instruction (RR)
> having a baseline of 1 second. It the proceeded to go through
> all of the instructions, RX, RS, SS etc. and then into I/O,
> MIH and so on. Have you ever heard or seen anything like
> this? I'm having trouble stressing the importance of poor I/O
> response time and I thought this might be of use."
>
> I had to tell him I hadn't ever seen such a thing, but would
> like to. I figure if anyone else alive knows what this
> is/was, they'll be on one of these two lists...!
>
> Anyone?
> --
> ...phsiii
>
> Phil Smith III
> Velocity Software
> www.velocity-software.com
> (703) 476-4511 (home office)
> (703) 568-6662 (cell)
>
