Diagnosing a slow Extract

Until now, we have discussed the performance of Replicat because this generally requires tuning, whether it be adjusting the integrated parameters or adding additional processes. Occasionally, however, the Extract process may be slow, but before we tune, we must diagnose. Typically, slow performance lies with I/O operations, but let's perform the following steps to find the root cause for our Extract running in the classic capture mode:

1. Firstly, collect the Extract's statistics using the STATS command:

   GGSCI (db12server01) 1>  stats EOLTP01, totalsonly *, reportrate sec
   GGSCI (db12server01) 2>  stats EOLTP01, totalsonly *, reportrate min
   

2. Copy the Extract's parameter file to a test parameter file as follows:

   $ cp ./dirprm/EOLTP01.prm ./dirprm/ETEST.prm
   

3. Add the TESTMAPPINGSPEED parameter to the test Extract parameter file, as shown in the following code:

   TESTMAPPINGSPEED
   REPORTCOUNT EVERY 5000 RECORDS
   

4. Add the test Extract process group ETEST with begin now timestamp...