The available extended private value is not control by any on the CA Symdump for CICS IN25OPTS trace format region parameters. It’s control by how the LPAR was configured by the Z/OS sysprog and it’s the amount of the available extended private storage that is available on the LPAR. When the trace format region is started the CA Symdump CICS code issues and Inquiry command to the operating system command LDAELIM to obtain the amount of available extended private storage. This value can be different on each LPAR unless the Z/OS sysprog team standardize the LDAELIM across LPAR all LPARS.
The CAIN5919 message indicates that the AVAILABLE EXTENDED PRIVATE storage that is available on the LPAR is greater than the IN25OPTS parameter TRCFMEGM and the trace format region starts. If the AVAILABLE EXTENDED PRIVATE storage was not greater than the IN25OPTS TRCFMEGM then the trace region would fail with message CAIN5920 INSUFFICIENT EXTENDED PRIVATE AREA TO START FORMAT TASK
MM/DD/YYYY HH:MM:SS AVAILABLE EXTENDED PRIVATE: NNNN MEGS
An informational message telling you what the available extended private storage area is for the TRACE FORMAT REGION. This value must be equal to or greater that the value specified in TRCFMEGM or the job will terminate.the trace format region is start
MM/DD/YYYY HH:MM:SS INSUFFICIENT EXTENDED PRIVATE AREA TO START FORMAT TASK
The available Extended Private area must be equal to or greater that the value specified in TRCFMEGM or the job will terminate.