As others have said, there are multiple ways to go look at what was using the CPU during a particular interval, depending on what tools you have access to and what the system configuration is. To recap:
SMF 30 interval (subtype 2 & 3) records will show CPU utilization by interval by address space. SMF/RMF 72 subtype 3 records will have utilization by service class and report class. Depending on how WLM is configured the report classes may be fairly granular or may be almost non-existant. RMF III's PROCU panel can be very handy for looking at processor utilization on a more granular timeframe in the recent past. (Assuming it is so configured.) Other system monitors such as SysView (which I know nothing of) or Omegamon usually have history recording capabilities that can be leveraged. However, I would submit that perhaps the more interesting question in this case is: "was the service class that the affected work was running in significantly delayed for some reason?" RMF III will again give you some insight into this via the DELAY panel. You have to be a little careful with that as there's no clear indication of the number of samples. (Although this tends to be a bigger issue on the enclave panel, because some enclaves tend to come and go rather quickly.) From an SMF perspective, the 72.3 records include details about the delay samples on a service class / report class basis. Finally, you mention that you know the code is good because it hasn't changed. But remember that the data may have changed over time; in particular the data volume may have changed. I have seen instances where the volume grew to a point that performance changed noticeably and relatively suddenly--because an extra level was added to an index or the data had grown disorganized or large enough that it crossed some threshold and the database optimizer started using a different access path. I'm not saying this is the case here, I just mention it as something to keep in mind. Scott ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN