6 IBM eServer zSeries 900 Technical Guide
Figure 1-3 Example of a multisystem server
The MCM on the z900 offers flexibility in enabling spare PUs via the Licensed Internal Code
Configuration Control (LICCC) to be used for a number of different functions. These are:
A Central Processor (CP)
An Integrated Facility for Linux (IFL)
An Internal Coupling Facility (ICF)
A System Assist Processor (SAP)
The number of CPs and SAPs assigned for particular general purpose models depends on
the configuration. A
standard configuration has the standard number of SAPs and a modified
configuration has more than the standard number of SAPs.
The number of spare PUs is dependent on how many CPs, SAPs, ICFs and IFLs are present
in a configuration. All z900 configurations have at least one spare PU.
The implementation of the 64-bit z/Architecture eliminates any bottlenecks associated with
lack of addressable memory by making the addressing capability virtually unlimited
Expanded Storage (ES) is still supported under 31-bit architecture. For 64-bit z/Architecture,
ES is supported by z/VM and guest systems running under z/VM. It is not supported by z/OS.