Chapter 1. IBM zSeries 990 overview 17
Draft Document for Review April 7, 2004 6:15 pm 6947ch01.fm
The proper number of CBU features, one for each “backup” CP, must be ordered and installed
to restore the required capacity under disaster situations. The CBU activation can be tested
for disaster/recovery procedures validation and testing.
Since this is a temporary upgrade, the original configuration must be restored after a test or
disaster recovery situation, via a concurrent CBU deactivation.
1.3.13 Performance
IBM's Large Systems Performance Reference method provides comprehensive
z/Architecture processor capacity data for different configurations of Central Processing Units
across a wide variety of system control program and workload environments. For zSeries
z990, z/Architecture processor capacity is defined with a 3xx notation, where xx is the
number of installed Central Processor (CP) units.
The actual throughput that any user will experience will vary, depending upon considerations
such as the amount of multiprogramming in the user's job stream, the I/O configuration, and
the workload processed. Therefore, no assurance can be given that an individual user will
achieve throughput improvements equivalent to the performance ratios shown in Figure 1-5.
For more detailed performance information, consult the Large Systems Performance
Reference (LSPR):
http://www.ibm.com/servers/eserver/zseries/lspr
Figure 1-5 Performance comparison, SW models, and HW models
MSU values for all z990 software models are found in URL:
Note: The CBU capability can coexist with On/Off CoD enablement. Both On/Off CoD and
CBU LIC-CC can be installed on a z990 server, but the On/Off CoD activation and CBU
activation are mutually exclusive.
Number of z990 CPs Base Ratio
1 CP z900-2C1 1.54 - 1.61
8 CPs z900-2C8 1.52 - 1.56
16 CPs z900-216 1.51 - 1.55
32 CPS z900-216 2.46 - 2.98
301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332
Model B16
Model D32
Model C24
* S/W Model refers to number
of installed CPs. Reported by
STSI instruction. Model 300
does not have any CPs.
* S/W
Model
Model A08