> -----Original Message----- > From: IBM Mainframe Discussion List > [mailto:[EMAIL PROTECTED] On Behalf Of Kelman, Tom > Sent: Friday, October 12, 2007 12:04 PM > To: [email protected] > Subject: Are there tasks that don't play by WLM's rules > > I am cross posting this to the IBM-Main and the MXG listservs. > > We are about to set the soft cap on our systems. I have been informed > by my system programmers that in the past they have seen tasks that > don't play by WLM's rules when it comes to resource > utilization. One is > the Direct-Connect (NDM) task. In the past, before I came to this > location, they saw Direct-Connect take CPU resources and affect CICS > processing when the system was heavily used even though Direct-Connect > had an importance level lower than the CICS regions. We are > running NDM > at an importance level of 4 with a velocity goal of 20. Our CICS > regions are at an importance level of 1 with a velocity goal > of 50. The > CICS transactions are run at an importance level of 1 with a response > time goal of 80% within 0.5 seconds. > > Has anyone else experienced this with Direct-Connect or any other > application? That is have they experienced the application > taking over > the system even though it has a low importance level? This > is important > to us as we want our CICS processing to be one of the last > things to be > hurt if we hit the soft cap. > > Tom Kelman > > Commerce Bank of Kansas City > > (816) 760-7632
In a sense, yes. I've had test batch perform better than production batch, despite a lower velocity and importance. The reason was that there was a single job running in the test service class and many jobs running in production. In this case, the PI of the test service class was greater than the PI of the production one, so WLM gave CPU cycles to the single test job. I don't have this particular problem with production CICS because I have marked the production CICS service class as CPU CRITICAL. This means that WLM will NEVER steal CPU cycles from CICS to help other, lower performance, work even if the CICS PI is smaller than the other work's PI. (PI is performance index. The smaller it is, the "better" the work in that service class is running. A PI of 1 means that the work is performing as specified in the service class. Less than 1 means that it is exceeding its performance specification. The larger the PI, the "worse" the service class is doing.) -- John McKown Senior Systems Programmer HealthMarkets Keeping the Promise of Affordable Coverage Administrative Services Group Information Technology The information contained in this e-mail message may be privileged and/or confidential. It is for intended addressee(s) only. If you are not the intended recipient, you are hereby notified that any disclosure, reproduction, distribution or other use of this communication is strictly prohibited and could, in certain circumstances, be a criminal offense. If you have received this e-mail in error, please notify the sender by reply and delete this message without copying or disclosing it. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
