Jon, thanks for the thoughtful reply. Much appreciated. You say the z900 is 1/8 as fast (powerful, whatever, fill in your favorite word) as the z9. That's a combination of two factors, right? Each CPU on the z9 is 1.48 times as fast as those on the z900, and in addition the -722 has 22 of them, while the -2C3 has only three, is that right? I am mostly interested at this moment in CPU time. I know it's not the only thing, and it's not the same thing as wall clock time, but it is what the company is going to be billed for so it is a (the?) critical factor at this moment. So I think my focusing on relative CPU speed rather than total "box power" (CPU's only, or CPU's and I/O) is correct at this time. Any thoughts?
Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Jon Butler Sent: Wednesday, July 18, 2012 11:12 AM To: [email protected] Subject: Re: Help with elementary CPU speed question As has been pointed out, there are many IBM tools such as zPCR that you can download to help with this exercise. The tools require either a good estimate or RMF data from the LPARs to give you an accurate comparison. In running one job anything can happen to distort the figures. However, I think a rough calculation without regard to the other work in the LPARs on the several CECs can give you an idea of what to expect. If we make the assumption that both CECs are running a similar workload....not bloody likely give the CEC's design difference, disk drives, I/O configs, WLM settings, OS version, etc....but using numbers from the latest MIPS ratings here is what you are up against: z9/722 rated at 1226 MSU z900/2C3 rated at 144 MSU I'd guess your job is going to run 1226/144 or 8 times slower. Let us know what happens. Of course if the z9 is running at 95% and the z900 at 5%, your job may be faster on the older CEC ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
