You may have heard of the Top500 list. It ranks the world’s 500 most powerful supercomputers based on their performance as measured by the Linpack benchmark. Published twice per year (in June and November) since 1993, the Top500 list records the development of supercomputers over the past two to three decades. In addition to performance, the Top500 list also summarises the main characteristics of the supercomputers in the list. Therefore, it contains much richer information than a mere ranking of the supercomputers by performance. In this post, we’ll have a closer look at the Top500 list and relevant topics, including supercomputers, performance, and statistics on processors and co-processors.

Supercomputer

The Top500 list is all about supercomputers. It therefore makes sense to have a brief overview of supercomputers before going into the details of the Top500 list. As shown in the image below, a supercomputer usually consists of many cabinets (also called racks), which are each about the size of a fridge. Each cabinet contains a stack of blades (with each blade being about the size of a PC turned sideways). Each blade has several compute nodes mounted in it, with each compute node having one or more multicore processors. For example, PDC’s Beskow system has 11 cabinets, 515 blades, 2,060 compute nodes, and a total of 67,456 cores . Because of their extraordinary computational capability, supercomputers have been used in many fields including molecular modelling, quantum mechanics, physical simulations, and climate research. This is vividly reflected in the design on the Titan supercomputer, which is still among the world’s top 10 most powerful supercomputers (as of the November 2018 Top500 list).

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