Yes, typically a task runs as a single TCB, and a TCB can only be dispatched on a single processor. I don't know if the logger spawns subtasks that could run on additional CPUs or not.
Rex -----Original Message----- From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Jason Cai Sent: Wednesday, July 12, 2023 5:27 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: [EXTERNAL] A question about CPU usage on z/OS Dear all, I have a question about CPU usage on z/OS that I hope you can help me with. Many years ago, we increased the CPU of a mainframe from one to four, but the batch jobs at night became slower. The explanation at that time was that a batch job could only use one CPU, and the single CPU performance decreased because of the increase to four CPUs. I accepted that explanation at that time. Now, twenty years later, is z/OS still the same that an address space like IXGLOGR can only use one CPU at most? Thank you for your time and attention. I look forward to hearing from you soon. Jason Cai ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- The information contained in this message is confidential, protected from disclosure and may be legally privileged. If the reader of this message is not the intended recipient or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any disclosure, distribution, copying, or any action taken or action omitted in reliance on it, is strictly prohibited and may be unlawful. If you have received this communication in error, please notify us immediately by replying to this message and destroy the material in its entirety, whether in electronic or hard copy format. Thank you. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
