Tracing memory and expanding log records

There are two new options for the TRACE operator command: mem and exp. The mem option allows you to trace memory problems in the log extract. The exp option allows you to display log records in the SYSPRINT output that were not expanded automatically by the DB2 Instrumentation Facility Interface (IFI). Both options are toggle switches.

Syntax

F REPJOB,E,TRACE=on|off|qid|mem|exp

Example of mem option output

TRACE=mem generates SYSPRINT output with a trace similar to this:

Example 2

MEMTRACE size   6000, at 0FBA6890 from 00006BA6. sp=  0. 
MEMTRACE size   22, at 0FA01998 from 00006C52. sp=  0.   
MEMTRACE size   122, at 0FAFA3C0 from 00006C52. sp=  0.  
MEMTRACE size   22, at 0FAFA3A8 from 00006C52. sp=  0.   
MEMTRACE size   122, at 0FAFA328 from 00006C52. sp=  0.  
MEMTRACE size   22, at 0FAFA310 from 00006C52. sp=  0.   
MEMTRACE size   122, at 0FAFA290 from 00006C52. sp=  0.

This trace shows a one-time request for a 6000-byte work area and storage for three reusable column header areas of 22 and 122 bytes. It also shows the length, the storage pointer, the displacement in the log extract that requested the storage, and the storage pool. If there is a memory problem in the log extract, this trace identifies it.

How the exp option works

TRACE=exp displays log records in the SYSPRINT output that were not expanded automatically by the IFI interface. These log records are expanded by Replication Agent for DB2 UDB using image copy compression dictionaries.

Occasionally, log record formats are modified by IBM to facilitate DB2 enhancements. These modifications may cause Replication Agent for DB2 UDB to have problems when expanding log records. If Replication Agent for DB2 UDB cannot expand a log record in this situation, Sybase Technical Support can use the display to help diagnose and fix the problem.