Health check was asking us to turn on XM=BEST as the region sensed zIIP processors.
Our question:
How does MAI make use of the zIIP?
We have turned on the 2 MAI's one with 2 zIIPs and the other without.
HS will monitor but the we would like to know what this is doing for MAI.
Is there specific doc for SOLVE:Access and the zIIPs turned on?
The manual supplies only generic information.
Release : 5.0
Component : SOLVE:Access Session Management
1. Only SRB processing can run over the ZIIP, not TCB processing so that limits what MAI can offload to zIIP.
2. We can't supply a 'maximum percentage' of zIIP utilization as that can vary depending on what functionalities of the product are most in use at a given customer site.
3. We did benchmarking for Netmaster which showed about 80% of the CPU ran on the zIIP (combined SSI and region) but have no such benchmarking for SOLVE:Access.
4. We have a minute minder parm you can set in the RUNSYSIN that provides the following information:
- the interval elapsed time. This is normally 60.00 or 15.00.
- the total preemptible SRB CPU time expended in the period.
- the total zIIP-eligible CPU time expended on normal CPs during the period.
- the total zIIP-eligible CPU time expended on zIIPs during the period.
- the percentage of total zIIP-eligible time that was actually expended on a zIIP.
That will show how much processing is being offloaded to the zIIP in one minute intervals.
TO IMPLEMENT:
In the PPREF section of your RUNSYSIN, add PPREF='XOPT=(CPU,CPUMM,CPULM)'
This cannot be changed dynamically; the region must be cycled to activate.
To see these same statistics every second, add PPREF='XOPT=(CPU,CPUMM,CPUMN)'
For more information on this please review KB 52645 How do I see zIIP statistics for Netmaster?
5. If you are using generic resources, see also KB 52444 How do I see zIIP statistics for the SSI region?