MEMLIMIT setting

Products

• IDMS
• IDMS - Database

Issue/Introduction

From the SDSF view, we can see that MEMLIMIT is defined for all CVs.

Some are set to 2G, while others are configured with NOLIMIT.

MEMLIMIT is not coded in the startup JCL, can you clarify where this setting is defined? 

Resolution

The MEMLIMIT allocated to a job is determined by z/OS not IDMS.

If you specify REGION=0K/0M, MEMLIMIT defaults to NOLIMIT.

If you specify REGION =nnnM and no MEMLIMIT parameter, the default is the value defined to SMF in SYS1.PARMLIB members SMFLIMxx and SMFPRMxx. In this case it defaults to 2G.

There is no need to hardcode a MEMLIMIT for the CV, it can be allowed to default.  

IDMS uses 64 bit storage when files in the DMCL or scratch are defined to use memory cache.

 

Additional Information

See IBM doc Relationship to the MEMLIMIT parameter and MEMLIMIT.