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Move IXX Buffers into 64-bit Memory

CA Datacom Version 14.0 allows the IXX buffer pool to be moved from 31-bit memory to 64-bit memory. In most z/OS sites, 31-bit memory is a limited resource while there is significant memory availability in 64 bit.

Business Value

Moving the IXX buffer pool to 64-bit memory frees up 31-bit storage that can be used to improve other MUF processes such as allocation of additional DXX and data buffers.

Additional Considerations

The SYSPOOL startup option at Version 12.0 has a parameter that is used to specify whether 31-bit or 64-bit memory is used to house the IXX buffers.

SYSPOOL cxxno,ixxno,dxxno,ixxbfrsize,31or64  

The IXX buffer location defaults to 31-bit memory.

For sites that have 64-bit memory available, we recommend that the IXX buffers be moved to 64-bit memory:

SYSPOOL cxxno,ixxno,dxxno,ixxbfrsize,64

The CA Datacom/DB Database and System Administration Guide contains a chapter on optimizing CA Datacom/DB performance. This chapter discusses techniques on how to monitor and tune the various CA Datacom/DB buffer pools. Review this information and other resources (such as the CA Datacom webcasts) to understand how to monitor and tune buffer specifications.