DB2 UDB for z/OS Version 8 Performance Topics - IBM Redbooks

The utilities ran on a G7 Turbo with ESS F20 DASD using z/OS V1.5. The table space
contains only one table with two indexes. The table space is a partitioned table space and so
one case involves using parallelism for the UNLOAD. The table used contains 124,999 rows.
The test cases are described in detail within Table 10-4.
Table 10-4 Unload test cases
Test case Description
Case 1 Unload from a table space using an image copy data set
Case 2 Unload from an image copy data set
Case 3 UNLOAD SELECT * FROM tablename
Case 4 UNLOAD SELECT C1, C2, C3, C4, C5 FROM tablename
Case 5 UNLOAD SELECT * FROM tablename WHERE C1 constant
C1 is a non-indexed column
Case 6 UNLOAD SELECT C1, C2, C3, C4, C5 FROM tablename WHERE C1 constant
C1 is a non-indexed column
Case 7 UNLOAD SELECT * FROM tablename WHERE C3 = constant
C3 is a non-indexed column
Case 8 UNLOAD SELECT * FROM tablename WHERE C4 constant
C4 is an indexed column
Case 9 UNLOAD SELECT * FROM tablename WHERE C4 = constant
C4 is an indexed column
Case 10 Same as Case 9 but used HPU parameter FORCE DB2
Parallel Run unload against multiple partitions of the same table space in parallel
HPU and UNLOAD utility
The results of the performance measurement between HPU and the DB2 V8 Unload utility
are summarized in Table 10-5.
Table 10-5 HPU V2.2 vs. DB2 V8 UNLOAD utility
Test case HPU V2.2 DB2 V8 UNLOAD % Difference
372 DB2 UDB for z/OS Version 8 Performance Topics
CPU Elapsed CPU Elapsed CPU Elapsed
Case 1 11.89 62 27.56 58 131.79 -6.45
Case 2 9.44 61 46.86 57 396.39 -6.55
Case 3 13.57 59 N/A N/A N/A N/A
Case 4 9.67 46 42.11 46 335.47 0.00
Case 5 18.00 58 33.02 57 83.44 -1.72
Case 6 13.93 46 47.10 50 238.11 8.69
Case 7 12.87 45 14.34 42 11.42 -6.66
Case 8 17.80 59 33.60 58 88.76 -1.69
Case 9 12.51 45 14.35 42 14.70 -6.66
Case 10 2.39 22 14.35 42 500.41 90.90