I believe its an enhanced version of inspect from omegamon z/os. It monitors where the cpu is spending its time in the code by sampling the restart psu for AS you are monitoring. It was created as a bet by an old mate of mine, a few moons ago.
<https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> On Wed, Apr 14, 2021 at 3:05 AM Colin Paice <[email protected]> wrote: > I used it about 10 years ago. We only looked at hot hot spots. Small hot > spots close to the background level, could change from day to day depending > on other usage. For example are the instructions/data cached in the local > processor? Changing the amount of optimization of the C code made a big > difference. Sometimes highly optimised code was slower than medium > optimised, because it optimised the whole program, whereas the hot code was > only about 5% of the total. Of course upgrade the processor, and > everything can change, bigger cache, bigger page size, TLB etc. > > I remember going to a customer to resolve a performance problem who was > going live in under 2 weeks. Using APA... > 1) The top usage in the top transaction was 80% in "printf". They still > had debug code running. > 2) Rather than use a variable in a dynamic SQL statement such as "select > from table where user=:userid", they had "select from table where > user='COLIN'", and "select from table where user='PAICE', so each of these > statements were unique, and could not be cached. > APA showed me these in the first hour (it made me look great). Once fixed, > the CPU dropped from 4 engines down to 1 engine for the same workload. > When I said they were going live in under 2 weeks; every one used the > password "qw", and I could logon to the super user using qw! > > Colin > > > > > > On Tue, 13 Apr 2021 at 16:56, Phil Smith III <[email protected]> wrote: > > > Colin Paice wrote: > > > > >I dont think it matters which machine you run on, you just run for a > > longer > > > > >time, and get more samples that way. > > > > > > > > There was, IIRC, also a maximum time for the sampling. What we wound up > > with > > was insufficient; as I noted, it was a while ago. Perhaps we missed > > something. > > > > > > ---------------------------------------------------------------------- > > For IBM-MAIN subscribe / signoff / archive access instructions, > > send email to [email protected] with the message: INFO IBM-MAIN > > > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN > -- ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
