In case you are curious about the definition of table t1, it has the same structure as syscat.columns and I inserted all the rows from syscat.columns four times into t1. Also, t1 is created under a DMS tablespace with the associated buffer pool of just 1000 4K pages.
The SQL statement took total 130.567 seconds. Out of which Agent CPU Time was 124.36 seconds, but what about the remaining time (6.207 seconds). Even if we assume that buffer pool read time is not inclusive in Agent CPU Time, still it does not sum up to total elapsed time.
I created a test script as shown in Listing 3:
I ran the script with the time command as shown below
Here is the content of test.out
Listing 6 shows the time related lines from the application snapshot