Herwig Elfering

System control structure of the IBM eServer z900

As computer systems become more complex, the use of embedded controllers for initializing and maintaining system operation is becoming increasingly prevalent. In the IBM eServer z900, a new control approach was introduced. This paper discusses why its introduction was necessary and outlines its associated, key technological and economic innovations. In particular, the following topics are addressed: service subsystem topology, hardware elements for performing system control, hardware abstraction, object-oriented framework for control, and internetworking of system control microprocessors.

IBM system z10 design for RAS

The IBM System z10™ server reliability, availability, and serviceability (RAS) design continues to reduce the sources of server outages through innovative RAS architecture and techniques. The z10™ server introduced functional improvements that challenged the RAS design. Increases were made in the performance of each processor, the total number of processors, the total size of the memory, the amount of cache, the bandwidth of the I/O, the thermal density, and the exposure to soft errors. These changes demanded stronger RAS functions to prevent unscheduled outages. Significant improvements were made to the IBM e-business on demand® functions (concurrent, customer-requested upgrades) that enable customers to better manage capacity without having to take planned outages. The hypervisor simplified configuration changes, such as adding cryptography or channel subsystems to logical partitions, by eliminating the need for preplanning. Single-core checkstopping and single transparent CPU (central processing unit) sparing were added. The RAS functions reduced the number of scheduled outages. Product improvements were complemented by improvements in RAS modeling. This paper describes these RAS improvements and how they provide value to the customer.

IBM system z10 firmware simulation

While a number of techniques to further improve firmware quality H. Elfering and design stability and to reduce firmware field problems over the long term were introduced with the IBM z900 and z990, a second wave of techniques were introduced for the IBM System z10™ platform. This paper describes the three new techniques: an enhanced static code analysis tool, code coverage, and simulation improvements.

Firmware verification and simulation in IBM zEnterprise 196

In IBM zEnterprise® 196, we introduced another set of firmware verification environments to enhance the verification coverage. In this paper, we discuss four affected areas: 1) virtualization of the support element, the hardware management console, and the flexible support processor; 2) test cases; 3) simulation of input/output adapter firmware; and 4) static analysis for millicode. These start another round in increasing verification coverage with the final goal of having all firmware components under simulation and test before the final system becomes available.