Evaluation of the zIIP feature requires neither zIIP processors nor even hardware that is capable of supporting zIIP processors. Use these steps to determine the benefits that can be achieved by using the zIIP feature.
Release: All supported releases.
Several easy steps are used to determine the benefits that can be achieved by using the zIIP feature as follows:
The SRB column from Step 2 is proportional to the number of MIPs of zIIP processing power that will be required to achieve these cost reductions
Examples
The following displays indicate that each run used between 93.5108 and 98.3110 CPU seconds of total normalized CPU.
The second run shows that 91.1222 CPU seconds out of a total of 93.5108 CPU seconds were offloaded to an SRB. Approximately one third of this SRB CPU time can be offloaded to a zIIP processor. For this particular application mix, approximately one third of the total CV CPU could be offloaded to zIIP processors.
Since a zIIP processor was present, the actual offloaded CPU can then be confirmed from the JES LOG Step End messages, IEF374I, which, in this case, indicates a total CPU reduction of 31.68 seconds.
Step 1 Output with ZIIP=N
NOTE: The Total CPU Time 98.3110 seconds is the sum of the TCB (00:01:38.3110)
+----------------------------------------------------------------------------------+
? ?
? *** Subtask display *** ?
? Subtask Elapsed time Total CPU time % CPU SRB ?
? Name TCB SRB TCB SRB TCB SRB ?
? -------- -------------- -------------- -------------- -------------- --- --- ?
? MAINTASK 00:00:14.0505 00:00:00.0000 00:00:02.3699 00:00:00.0000 16 N/A N ?
? SUBT0001 00:00:00.0122 00:00:00.0000 00:00:00.0104 00:00:00.0000 85 N/A N ?
? SUBT0002 00:00:00.0175 00:00:00.0000 00:00:00.0131 00:00:00.0000 74 N/A N ?
? SUBT0003 00:00:00.2348 00:00:00.0000 00:00:00.0398 00:00:00.0000 16 N/A N ?
? SUBT0004 00:00:00.2175 00:00:00.0000 00:00:00.0240 00:00:00.0000 11 N/A N ?
? SUBT0005 00:01:42.0081 00:00:00.0000 00:01:35.8538 00:00:00.0000 93 N/A N ?
? -------- -------------- -------------- -------------- -------------- --- --- ?
? Totals 00:01:56.5406 00:00:00.0000 00:01:38.3110 00:00:00.0000 84 N/A ?
? ?
+----------------------------------------------------------------------------------+
JES LOG Step End Message
+----------------------------------------------------------------------------------+
? IEF374I STEP/DCV /STOP 2008242.0425 CPU 1MIN 39.53SEC SRB ?
? 0MIN 11.73SEC VIRT 7840K SYS 552K EXT 56072K SYS 11460K ?
+----------------------------------------------------------------------------------+
NOTE: CPU 1MIN 39.53SEC + SRB 0MIN 11.73SEC = 111.26SEC
Step 2 Output with ZIIP=Y
NOTE: The amount of CPU seconds that was offloaded to an SRB is 91.1222. The Total CPU Time 93.5108 is the sum of the TCB (00:00:02.3886) and SRB (00:01:31.1222) added together.
To calculate the amount of CPU seconds that were offloaded to an SRB subtract the total TCB (00:00:02.3886) from the Total CPU Time (93.5108).
+----------------------------------------------------------------------------------+
? ?
? *** Subtask display *** ?
? Subtask Elapsed time Total CPU time % CPU SRB ?
? Name TCB SRB TCB SRB TCB SRB ?
? -------- -------------- -------------- -------------- -------------- --- --- ?
? MAINTASK 00:00:12.9116 00:00:00.0434 00:00:02.1387 00:00:00.0525 16 120 Y ?
? SUBT0001 00:00:00.0125 00:00:00.0000 00:00:00.0111 00:00:00.0000 88 N/A Y ?
? SUBT0002 00:00:00.0118 00:00:00.0002 00:00:00.0103 00:00:00.0000 87 00 Y ?
? SUBT0003 00:00:00.1643 00:00:00.0014 00:00:00.0624 00:00:00.0016 37 114 Y ?
? SUBT0004 00:00:00.0276 00:00:00.0004 00:00:00.0239 00:00:00.0008 86 200 Y ?
? SUBT0005 00:00:00.3849 00:01:17.1037 00:00:00.1422 00:01:31.0673 36 118 Y ?
? -------- -------------- -------------- -------------- -------------- --- --- ?
? Totals 00:00:13.5127 00:01:17.1491 00:00:02.3886 00:01:31.1222 17 118 ?
? ?
+----------------------------------------------------------------------------------+
JES LOG Step End Message
+----------------------------------------------------------------------------------+
? IEF374I STEP/DCV /STOP 2008242.0400 CPU 1MIN 01.60SEC SRB ?
? 0MIN 17.98SEC VIRT 7840K SYS 552K EXT 56080K SYS 11500K ?
+----------------------------------------------------------------------------------+
NOTE: CPU 1MIN 01.60SEC + SRB 0MIN 17.98SEC = 79.58SEC
Subtracting the total offloaded CPU from the STEP2 IEF374I message (79.58), from the total offloaded CPU from the STEP1 IEF374I message (111.26) indicates a total CPU reduction of 31.68 seconds.