On Tuesday, 02/21/2006 at 04:32 CET, Eginhard Jaeger <[EMAIL PROTECTED]> wrote: > Note, however, that statistically relevant wait state information is best > obtained from CP monitor data. And the easiest way to convert CP monitor > data to numbers you can understand is to use a performance monitor ..
Trying to manage the performance characteristics of a z/VM system without using some sort of performance management kit is like entering the boxing ring with *both* hands tied behind your back. CP INDICATE commands provide a snapshot (sometimes instantaneous, sometimes smoothed) of CP control block contents, really. They don't give tell you how many times some Very Interesting event happened in some relevant interval of time and you don't see trends. You can see "I have a problem", but you can't readily identify its source. Granted, some people with years of VM experience can ferret out the source, but its a rare gift. It's the same reason I still teach TCP/IP routing at conferences: It's information you need to know when something *goes wrong*. Performance management tools let you find out not only *what* is happening, but *why*. 'Good Performance' is a qualitative term: - It's relatative only to 'Bad Performance' - It depends on properly functioning hardware and software - It depends on sufficient raw resources - It depends on the correct allocation of those resources The CP INDICATE command really can't provide you with warm fuzzies on all those points. Alan Altmark z/VM Development IBM Endicott
