This is the sixth edition of a report in which we attempt to give an overview of parallel- and vector systems that are commercially available or are expected to become available within a short time frame (typically a few months to half a year). We choose the expression ``attempt'' deliberately because the market of parallel- and vector machines is highly evasive: the rate with which systems are introduced -- and disappear again -- is very high and therefore the information will probably be only approximately valid. Nevertheless, we think that such an overview will be useful for those who want to obtain a general idea about the various means by which these systems strive at high performance, especially when it is updated on a regular basis.
We will try to be as up-to-date and compact as possible and on these grounds we think there is a place for this report. The present report will be somewhat shorter than earlier ones: at this moment systems are disappearing at a faster rate than new ones replace them. The reasons for this seem to be threefold:
These effects make the high-performance computing scene somewhat more clear (and also somewhat less adventurous). Still, the supercomputer market is very dynamic and we too, cannot hope give a complete report for the reason already mentioned above: the speed with which companies and systems appear and disappear makes this almost impossible. However, by updating the report we can at least follow the main trends in popular and emerging architectures.
The rules for including systems in this report are as follows: they should be either available commercially at the time of appearance of this report, or within 6 months thereafter. This is to avoid confusion by describing systems that are announced much too early, just for marketing reasons and that will not be available to general users within a reasonable time. We also have to refrain from including all generations of a system that are still in use. Therefore, for instance, we do not include the Convex C3000 series, the Cray Y-MP series, or the Thinking Machines CM-5 anymore although these systems are still used widely. Generally speaking, we include machines that are still marketed or will be marketed within 6 months. In this issue we add for the first time Wold Wide Web addresses of vendors. The information on the Web pages of the vendors may be more recent than what can be provided in this report. On the other hand such pages should be read with care because it will not always be clear what the status is of the products decscribed there.
We order the systems by their various architectural classes, which should facilitate to find the information of systems that belong to a certain class. We also omit the price information which in most cases is next to useless. If available, we will give some information about performances of systems based on user experiences instead of only giving theoretical peak performances. Here we have adhered to the following policy: We try to quote best measured performances, if available, thus providing a more realistic upper bound than the theoretical peak performance. We hardly have to say that the speed range of supercomputers is enormous, so also the best measured performance will not always reflect the performance of a reader's favorite application. When we give performance information, it is not always possible to quote all sources and in any case if this information seems (or is) biassed, this is entirely the responsibility of the author of this report. He is quite willing to be corrected or to receive additional information from anyone who is in the position to do so.
Before giving a recount of the systems proper, we first define the architectural classes and some other terms in section 2 which will be used in section 3 in the description of the machines. In section 4 some systems are listed that disappeared from the market and in section 5 we present some systems that are under development and have a fair chance to appear on the market.
The overview given in this report concentrates on the computational capabilities of the systems discussed. To do full justice to all assets of present days high-performance computers one should list their I/O performance and their connectivity possibilities as well. However, the possible permutations of configurations even for one model of a certain system often are so large that they would multiply the volume of this report, which we tried to limit for greater clarity. So, not all features of the systems discussed will be present. Still we think (and certainly hope) that the impressions obtained from the entries of the individual machines may be useful to many. We also omitted some systems that may be characterised as ``high-performance'' in the fields of database management, real-time computing, or visualisation. Therefore, as we try to give an overview for the area of general scientific and technical computing, systems that are primarily meant for database retrieval like the AT&T GIS systems or concentrate exclusively on the real-time user community, like Concurrent Computing Systems, are not discussed in this report.
Although most terms will be familiar to many readers, we still think it is worthwhile to give some of the definitions in section 2 because some authors tend to give a meaning that may slightly differ from the idea the reader already has acquired.