SMS (buffer use) trace

The storage management services (SMS) trace records contain information on the use and availability of VTAM® buffer pools. SMS trace records are written after a predetermined number of requests occur for VTAM buffers. An IBM-supplied threshold causes a trace record to be written after every 1000 requests.

Note:

If the DISPLAY BFRUSE command is issued while this trace is running, the fields MAX TOTAL, MAX USED, and TIMES EXP in the output for DISPLAY BFRUSE reflect buffer usage only since the last trace record was written, because the SMS trace resets these fields.
The SMS trace is not the same thing as the VTAM internal trace with the SMS option specified. The SMS trace is similar to the DISPLAY BFRUSE command. The SMS trace displays in trace output the same information that the DISPLAY BFRUSE command displays on the screen.