A Spanish Museum Built a Cray-1 Replica From 30 Mac Minis — and It Reaches 1.3 Teraflops

October 10 (IT Home) — The technology outlet Ars Technica published a post yesterday (9 October) reporting that, to mark the 50th anniversary of the Cray-1 supercomputer and the 50th anniversary of Apple’s founding, Spain’s computer history museum built a visual replica of the Cray-1 out of 30 2012-model Apple Mac minis, a project that took 18 months.

IT Home notes: the Cray-1 was a supercomputer designed by the American company Cray Research, led by the computer designer Seymour Cray. The first system was installed at Los Alamos National Laboratory in the United States in 1976; from 1976 to 1982, the Cray-1 remained the fastest computer in the world.

The Cray-1 had a clock speed of 80 MHz and about 8 MB of main memory, with a theoretical peak performance of roughly 160 million floating-point operations per second, or 160 megaflops. It used a 64-bit word length and boosted vector operation speed through dedicated registers and a pipelined design.

To mark the 50th anniversary of the Cray-1 and also to celebrate Apple’s 50th anniversary, Spain’s computer history museum used 30 2012-model Mac minis to build a 1:1 visual replica of the Cray-1, which took 18 months and is now on public display at the museum.

The replica consists of five quad-core i7 machines and 25 dual-core i5 machines. In its most recent test, using 64 active processing cores, it achieved an overall performance of 1.3 teraflops. The cluster runs macOS Mojave (10.14) and uses the Message Passing Interface (MPI) to pass tasks between nodes. Visitors can watch the system run matrix algorithms and observe how performance changes between single-core and multi-node parallel operation.

The museum mounted the 30 Mac minis vertically on steel frames and aluminium brackets, using natural convection from rising hot air for cooling. The museum says the cluster is almost silent; the two Gigabit Ethernet switches at the bottom of the exhibit are the main source of noise, at about 30 to 33 decibels.