On the appropriateness of commodity operating systems for large-scale, balanced computing systems

In the past five years (1997-2002), we have been involved in the design and development of Cplant™. An important goal was to take advantage of commodity approaches wherever possible. In particular, we selected Linux, a commonly available operating system, for the compute nodes of Cplant™. While the use of commodity solutions, including Linux, was critical to the success of Cplant™, we believe that such an approach will not be viable in the development of the next generation of very large-scale systems. We present our definition of a balanced system and discuss several limitations of commodity operating systems in the context of balanced systems. These limitations are categorized into technical limitations (e.g., the structure of the virtual memory system) and social limitations (e.g., the kernel development process). While our direct experience is based on Linux, issues we have identified should be relevant to all commodity operating systems.