Specifications

5102ch04.fm Draft Document for Review May 12, 2014 12:46 pm
108 IBM Power System S822 Technical Overview and Introduction
4.1 Reliability
Highly reliable systems are built with highly reliable components. On IBM POWER
processor-based systems, this basic principle is expanded upon with a clear design for
reliability architecture and methodology. A concentrated, systematic, architecture-based
approach is designed to improve overall system reliability with each successive generation of
system offerings.
4.1.1 Designed for reliability
Systems that are designed with fewer components and interconnects have fewer
opportunities to fail. Simple design choices such as integrating processor cores on a single
POWER chip can dramatically reduce the opportunity for system failures. The POWER8 chip
has more cores per Processor module and also the I/O Hub Controller is integrated in the
Processor core. That generates a PCIe BUS directly from the Processor module.
Parts selection also plays a critical role in overall system reliability. IBM uses three grades of
components with grade 3 being defined as industry standard (“off-the-shelf” components). As
shown in Figure 4-1, using stringent design criteria and an extensive testing program, the IBM
manufacturing team can produce grade 1 components that are expected to be 10 times more
reliable than industry standard. Engineers select grade 1 parts for the most critical system
components. Newly introduced organic packaging technologies, rated grade 5, achieve the
same reliability as grade 1 parts.
Figure 4-1 Component failure rates
4.1.2 Placement of components
Packaging is designed to deliver both high performance and high reliability. For example,
the reliability of electronic components is directly related to their thermal environment. That
is, large decreases in component reliability are directly correlated with relatively small
increases in temperature. All POWER processor-based systems are carefully packaged to
ensure adequate cooling. Critical system components such as the POWER8 processor chips
are positioned on the planar so that they receive clear air flow during operation. In addition,
POWER processor-based systems are built with redundant, variable-speed fans that can