NULL or dynamic PDEs in use by a CV

Products

• IDMS

Issue/Introduction

There is no command to display the number of NULL or dynamic PDEs that an active CV is using. This article describes a process for doing so.

Environment

Release: All supported releases.

Resolution

After the CV starts up, issue the command DCMT DISPLAY MEMORY PDT +8 % 16. This displays the header for the TIX (internal storage index) of the program definition table.

      D MEM PDT +8 % 16
 <Addr>   <Offset>                 <Hex>                    <Character>
40FCB008  00000000  E3C9E75C 01A00000 00000681 0000005F  *TIX*.......a....*

The value at offset x'C' is the number of free slots in the PDT. In this example, it is x'5F', or 95.

At any time during the life cycle of the CV, run the command again.

      D MEM PDT +8 % 16 
 <Addr>   <Offset>                 <Hex>                    <Character>
40FCB008  00000000  E3C9E75C 01A00000 00000681 0000005C  *TIX*.......a...**

There are now only x'5C', or 92, free slots in the PDT.

Subtract this value from the number found at startup. 95 - 92 means there are 3 NULL or dynamic PDEs in use by the CV at the time the second command was issued.