We've got a legacy system that runs VSI I64VMS OPENVMS V8.4-2L1 on an OpenVMS cluster and with the following CPU config:
Code: Select all
XXXXX (VMS2) $ show cpu/all System: VMS2, HP Integrity BL860c i4 (1.73GHz/20.0MB) CPU ownership sets: Active 0-7 Configure 0-7 CPU state sets: Potential 0-7 Autostart 0-7 Powered Down None Not Present None Hard Excluded None Failover None XXXXX (VMS2) $
Many years ago we used to run the app on VAX/VMS with, I believe, only one CPU and a design decision then was taken to use the sys$process_affinity system service to set the affinity to CPU 0, and this now appears to be a bottleneck, and that the other 7 CPUs are not being used.
If we were to make changes such that some of the executables were to set affinity to other CPUs, do you see any potential problems? At the moment we're looking at possible changes to stop some of our processes hogging the CPU at 75%+ sometimes.
I'd really welcome any comments, caveats. I can provide more info as needed.