With the ideal combination of now zIIP enabling both your batch applications and your TP application, you can achieve optimum results and reduce the overall total cost of computing on the z/OS system.
| Issue 2, 2017 |  Download PDF |
The Natural zIIP Enabler for Batch was the first in a series of products that takes advantage of IBM’s specialty processors. By moving Natural workload from IBM General Purpose Processor (GPP) to less expensive IBM® zIIP™ processors for execution, the Natural zIIP Enabler provides a low-cost alternative to increasing capacity on your existing GPPs when you reach your z/OS® capacity limit. Meanwhile, following the introduction of the Natural zIIP Enabler for Com-plete, we released in April 2017 the Natural zIIP Enabler for CICS®.
With the ideal combination of now zIIP enabling both your batch applications and your TP application, you can achieve optimum results and reduce the overall total cost of computing on the z/OS system.
How does it work?
Quite similar to the Natural zIIP Enabler for Batch, the new Natural zIIP Enabler for CICS moves, during Natural runtime, the eligible workload from the GPP to a zIIP processor by switching to Service Request Block (SRB) execution mode whenever possible. No source changes or other changes to your Natural applications are required. To activate the zIIP mode, the profile parameter ZIIP (values: AUTO/ON/OFF) must be set. Alternatively the parameter can be set in the NTZIIP macro.
This is now possible with the version of the Natural CICS Interface NCI v8.3.3. and the recommended version of Natural is NAT v8.2.6. This means that CICS TS 4.2 is the minimal version, as all earlier versions are not supported by NCI v8.3.3 due to the end-of-maintenance dates of these CICS TS versions. For running OTE, the NCI front-end program must be defined to CICS as “Threadsafe” and “OpenAPI” which means that Natural sessions can run simultaneously in multiple threads. If you are calling 3GL programs from a Natural program, there might be some adaptations required to the 3GL programs dependent upon the way your programs are called. The conditions running “Threadsafe” under CICS are described in Threadsafe Considerations for CICS .
Fig1: Natural zIIP Enabler for CICS
Support for Adabas client add-ons
Another major enhancement available with the April 2017 release is, that the Adabas link routine and the Adabas add-on client products are zIIP enabled. Natural zIIP Enabler for CICS checks, via the Adabas link module, if the Adabas link routine is prepared for zIIP processing. If yes, Natural zIIP calls the Adabas link routine in SRB mode and the Adabas Client Add-on is running on the zIIP processor. Supported products include Adabas FastPath, Adabas Vista, Adabas Transaction Manager, Adabas SAF Security and Adabas Review. For the Natural zIIP Enabler for Com-plete, the support of Adabas client add-ons is planned for the October 2017 release.
How do I know if I am running on the zIIP?
You can easily check that your Natural system is able to run on the zIIP processor. Assuming the license keys for the Natural ZIIP Enabler have been installed correctly, the following message must appear on the Message Log Destination MSGDEST: NAT7070 Advanced zIIP support enabled successfully. As an alternative, you can also issue the Natural system command ZIIP. If zIIP support is active, a zIIP Processing Information report is displayed indicating that zIIP support has been enabled. If zIIP support is not active, please check if you have installed the correct license key for NAZCI.
zIIP statistics
The Natural system command zIIP can also be used to show zIIP statistic and analyze your CPU savings using the Natural zIIP Enabler. The command displays the number of GCPs (General Central Processors) and zIIPs available in your z/OS environment. You can see the CPU time consumed and also get a list of components that are causing SRB/TCB switches, meaning switching to the zIIP and switching back again.
Fig.2: zIIP Processing Information Using the zIIP System Command
Fig.3: zIIP Switch Statistics
And more news
With the Natural for CICS Interface (NCI) 8.3.3, the code will be delivered the first time as object code only. This provides many advantages for customers. The installation becomes much easier, because an assembly of the NCI code is no longer required. User exits will be provided enabling customers to add their own code to the NCI interface. The special parameter module NCIPARM for CICS has been integrated as macro NTCICSP into the NATPARM module to ease the administration of parameter. With the upcoming release in October 2017, a new roll server for Natural will be introduced and Natural zIIP for CICS can benefit even more using this new technology. For more information please check TECHNIQUES article “Lower your mainframe TCO” in issue #3, 2016.