Introduction and Objectives

Statistics on high-performance computers are of major interest to manufacturers, users, and potential users. These people wish to know not only the number of systems installed, but also the location of the various supercomputers within the high-performance computing community and the applications for which a computer system is being used. Such statistics can facilitate the establishment of collaborations, the exchange of data and software, and provide a better understanding of the high-performance computer market.

Statistical lists of supercomputers are not new. Every year since 1986 Hans Meuer has published system counts of the major vector computer manufacturers, based principally on those at the Mannheim Supercomputer Seminar. Statistics based merely on the name of the manufacturer are no longer useful, however. New statistics are required that reflect the diversification of supercomputers, the enormous performance difference between low-end and high-end models, the increasing availability of massively parallel processing (MPP) systems, and the strong increase in computing power of the high-end models of workstation suppliers (SMP).

To provide this new statistical foundation, we have decided in 1993 to assemble and maintain a list of the 500 most powerful computer systems. Our list has been compiled twice a year since June 1993 with the help of high-performance computer experts, computational scientists, manufacturers, and the Internet community in general who responded to a questionnaire we sent out; we thank all the contributors for their cooperation. We have also used parts of statistical lists published by others for different purposes.

In the present list (which we call the TOP500), we list computers ranked by their performance on the LINPACK Benchmark. While we make every attempt to verify the results obtained from users and vendors, errors are bound to exist and should be brought to our attention. We intend to continue to update this list half-yearly and, in this way, to keep track with the evolution of computers. Hence, we welcome any comments and information; please use the following mail form. The list is freely available at http://www.top500.org/ where you can create additional sublists and statistics out of the TOP500 database on your own. Here you also have access to slides dealing with the interpretation of the present situation as well as with the evolution over time since we started this project.

The main objective of the TOP500 list is to provide a ranked list of general purpose systems that are in common use for high end applications. The authors of the Top500 reserve the right to independently verify submitted LINPACK results, and exclude systems from the list which are not valid or not general purpose in nature. By general purpose system we mean that the computer system must be able to be used to solve a range of scientific problems. Any system designed specifically to solve the LINPACK benchmark problem or have as its major purpose the goal of a high Top500 ranking will be disqualified.