Set the REGION parameter
on the EXEC card in the JCL according to the virtual storage requirements
for thread and Java™ heap
settings in the Gateway daemon.
For more information about calculating the required setting see Tuning the gateway to avoid out of memory conditions.
To verify the actual region size allocated for the CICS Transaction Gateway, include
the CTGDBG DUMMY DD statement in the JCL step for CTGBATCH. Message
CTG0813I shows the current region size.
The following parameters can also limit the values that you can
choose for the REGION parameter:
- The ASSIZEMAX parameter of the OMVS segment of a RACF® user
ID; for more information see the RACF Command Language Reference.
- The UNIX System Services MAXASSIZE parameter found in SYS1.PARMLIB(BPXPRMxx);
for more information see the UNIX System Services Planning.
The value specified for ASSIZEMAX overrides any value provided by
the MAXASSIZE parameter
Note: Use of REGION=0M. The actual region size available when
REGION=0M is used is unpredictable, due to optional implementation
of the system exit routine IEFUSI. REGION=0M indicates that the address
space must be given as much memory as possible. However, large REGION
sizes might be policed by the IEFUSI exit, and reduced to a default
size. If this default size is too small the CICS Transaction Gateway
is likely to fail with out of memory problems.