IBM z/15 T01 & T02

The IBM z/15 T01 has five variants with the model number indicating the maximum number of processor cores; and the models are: Mod34, Mod71, Mod108, Mod145, and Mod190.

IBM recently announced the z/15 T02 which overlaps the low end of the T01, again with five models; Mod4, Mod13, Mod21, Mod31 and Mod65.

Cores are configurable and their functions are described opposite.

To aid resilience, and permit 24 by 7 hour operation, mainframes can be linked to form a Sysplex. In a Sysplex, a failing system's work can be taken over by another system, which avoids a break in service. A Sysplex requires a Coupling Facility which may be stand-alone, or an ICF.

z/Series Processor Complex

An IBM z/15 T01 processor comes in 1 of 5 models, with the largest having 190 configurable cores which can be used as:

CP - Traditional Central Processor
ICF - Internal coupling Facility
- used for SysPlex co-ordination
IFL - Integrated Facility for Linux
SAP - System Assist Processor
- Every modern mainframe has at least 1 SAP, and larger systems may have more.
  The SAPs execute internal code to provide the I/O Subsystem.
ZAAP - Application Assist Processor
ZIIP - Integrated Information Processor
- Dedicated processor designed to operate asynchronously with the general CPs to process new workloads: manage containers and hybrid cloud interfaces; and more.