Rotational Position Sensing Regards, Richard Schuh
-----Original Message----- From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On Behalf Of Marty Zimelis Sent: Thursday, November 08, 2007 11:11 AM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: Poster of computer hardware events? 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: IBMVM@LISTSERV.UARK.EDU > 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) >
