Scaling Solaris for Enterprise Computing

Cray Business Systems chose the Solaris/XDBus platform to develop the Cray Superserver 6400 (CS6400), which is today’s largest Symmetric Multi-Processing (SMP) server. Our strategy was to leverage most of the system design and implementation from outside vendors, and to focus our engineering resources on adding value to a base design. We have scaled the hardware interconnect and Solaris operating system to support 64 processors and 16 gigabytes of memory. We added a System Service Processor which supports numerous RAS features, and added a tape subsystem and a math library that are based on widely-used UNICOS features. 1 Choosing our technology leverage In November 1991, Cray Research and Sun Microsystems entered into a technology partnership to leverage their complementary strengths across the broader marketplace. As a result of that partnership, Cray formed the Cray Business Systems Division to develop a Solaris/SPARC platform that was scaled larger than Sun’s own platforms, and to take the product into markets new to Cray Research. The goal of our division is to develop unique products using primarily leveraged technology. Our plan is to build only the components of the system that provide unique added value. 1.1 Solaris/SPARC strengths We received four main benefits from the use of Sun’s Solaris/SPARC technology base: 1. The most applications . Solaris has the largest installed base of any Unix, and has a catalog of over 9,000 native applications. 2. The best multi-processor Unix . Sun Microsystems has sold the most multiprocessor systems of any vendor. SunSoft has aggressively threaded Solaris in support of Sun’s multiprocessor systems, which scale up to 20 processors. 3. An openly available Unix . Sun Microsystems has established a separate company, SunSoft, which has the mission of supplying the Solaris operating environment to the industry. 4. An interconnect chipset . Sun Microsystems and Xerox designed the XDBus interconnect chipset for medium and large servers. Sun decided to develop products using only one or two buses, even though the XDBus chipset could handle four buses. Figure 1: Solaris/SPARC strengths 1.2 Our value-added strategy We focused our engineering developments in three areas: 1. Pushing the performance envelope of symmetric multiprocessing . We implemented the CS6400 using all four of the XDBuses. We designed the centerplane ASICs necessary to drive the four XDBuses across a bigger system, and increased the bus clock from 40 MHz to 55 MHz. With this nearly three-fold increase in memory bandwidth to 1.3 Gbytes per second, we scaled our system size up to 64 processors — the most of any SMP system. 2. Improving system availability and serviceability . The CS6400 is built out of a small number of component types which can be configured in parallel to minimize the impact of most system failures. We added the ability to dynamically Solaris Largest volume Unix Leading SMP Unix Open availability from SunSoft The best SMP interconnect chipset Copyright © Cray Research Inc. All Rights Reserved