A system programmer can use the TDP DISPLAY CELLS command to monitor the performance of the TDP cell system. TDP will display the following cell system statistics in response to the DISPLAY CELLS command:
- Size of cells in use
- Number of each size of cell allocated to TDP
- Number of each size of cell currently in use
- Maximum number of each size of cell used at any one time
- Number of times GETMAIN was used to satisfy requests because all cells allocated were in use
- Number of cross memory cells initially in use
- Number of times that a TDP subtask was placed into a wait because all cells of that size were in use
View final statistics in the following records:
- In z/OS, the SMF shutdown record
- In VOS3, the SMS record
If this information indicates that the number of cells currently allocated is not adequate for certain kinds of processing, more cells can be provided to the memory manager. Cells can be added during TDP startup by using the ADD CELLS operator command, which can be executed from the TDPPARM data set, or from the system console.
For example, if the statistics indicate problems in any client performance for FastLoad operations, a systems programmer can decide to add cells of data buffer size before running the next FastLoad.