HPC Architecture

At NSA, the HPC operating environment is split between UNIX and our home-grown operating system, Folklore, and its higher-level language, IMP. The latter is still in use on some systems and will only disappear when the systems disappear.

The HPC architecture in a complex consists of the elements shown in Figure 1. As stated before, both Folklore and UNIX are in use. About five or six years ago, NSA detached users from direct connection to supercomputers by giving the users a rich variety of support systems and more powerful workstations. Thus, HPC is characterized as a distributed system because of the amount of work that is carried out at the workstation level and on user-support systems, such as CONVEX Computer Corporation machines and others, and across robust networks into supercomputers.

NSA has had a long history of building special-purpose devices that can be viewed as massively parallel processors because most of them do

Figure 1.
NSA's HPC architecture in the 1990s.

very singular things on thousands of processors. Over the past few years, NSA has invested a great deal of effort to upgrade networking and storage capacity of the HPC complexes. At present, a major effort is under way to improve the mass-storage system supporting these complexes. Problems abound in network support. Progress has been slow in bringing new network technology into this environment because of the need to work with a large number of systems, with new protocols, and with new interfaces. A great deal of work remains to be done in this field.