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MainView for CICS
MainView for CICS
MainView for CICS : All Versions
What factors impact the CPU consumption of MainView for CICS?
Generally, the CPU usage of MainView for CICS tracks with the following items:
- The number of targets
- The number of transactions when using TASKKILL
- The number of views
- The number of CHISTORY views
- The number of Workloads
To minimise the overhead of MainView for CICS we recommend the following:
- Specify TASKKILL=NO in the SOPT unless it is necessary. This exit is called for every EXEC CICS call made by every transaction. It is useful when needed, but drives overhead when not really needed.
- Minimise the number of users who drive CHISTORY views
- Check the use of MainView Explorer configurations running with Auto refresh, 3270 screens running in Automatic Screen Update (ASU) mode or MainView Alarms. These can all consume a considerable amount of CPU over time in a MainView Product Address Space (PAS). All of these have the same effect as a user constantly hitting Enter and can lead to excessive processing of the data by the “data selectors”. This can generate overhead due to the work involved in creating the view on every refresh, particularly if unfiltered, with a small/short refresh interval or a Context of All.
- Try not to define a workload unless you really need it. These can drive CPU usage.
- Utilise the USEZIIP parm, this provides the ability to offload the processing of the product data collection monitors to zIIPs. Enabling zIIP processing instructs the code for product monitors to run as zIIP-eligible service request blocks (SRBs) in the target IBM CICS (or IBM IMS) regions. During PAS initialisation a zIIP eligible enclave is created for the purpose of offloading the monitor SRBs for CICS (and IMS) to zIIP processor. The PASINFO view shows how much processing has been offloaded by MV for CICS and MV for IMS (see PTF BPL2054 and Tech Bulletin - http://documents.bmc.com/supportu/documents/14/68/241468/241468.pdf)
- Eliminate unwanted CICS SMF 110 records if you do not need them. You can suppress CICS writing performance records for transactions by specifying MN=OFF, MNPER=OFF and MNEXC=OFF in the SIT. This will not affect MVCICS writing its CMRDETL records.
- Check that your CMRDETL datasets are not filling up and switching too frequently. This can cause overhead.
- Avoid using Program Timing unless you need it. Program Timing has to be manually started, you cannot set it on during start-up in CMRSOPT.
- Avoid using Session Collection unless you need it to diagnose a problem.
BMC Software recommends customers to stay current on maintenance and product version to avoid encountering known problems.
- Review product notices on the Customer Support website at http://www.bmc.com/support_home
- Register for proactive alerts to receive e-mail notification when product notices are issued or updated.
- MainView for CICS