Convex Computer: Difference between revisions

Revision as of 07:20, 30 August 2009

Revision as of 07:30, 30 August 2009

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Their first machine was the '''C1''', released in 1985. The C1 was very similar to the [[Cray-1]] in general design, but used a slower, less expensive CMOS memory and main CPU. They offset this by increasing the capabilities of the vector units, including 128 64-bit registers. It also used [[virtual memory]] as opposed to the '''static memory''' system of the Cray machines, which improved programming. It was generally rated at 20 MFLOP/s peak for double precision (64 bits), and 40 MFLOP/s peak for single precision (32 bits), about 1/5th the normal speed of the Cray-1. They also invested heavily in advanced automatic vectorizing [[compiler]]s in order to gain performance when existing programs were ported to their systems. The machines ran a [[BSD]] version of [[Unix]] known initially as '''Convex Unix''' then later as '''ConvexOS''' due to trademark/licensing issues. ConvexOS has DEC VMS compatibility features as well as Cray Fortran features. Their Fortran compiler went on to be licensed to other computers such as the Ardent and Stellar (and merged Stardent).

The '''C2''' was a crossbar-interconnected [[multiprocessor]] version of the C1, with up to four CPUs, released in 1988. It used newer 20,000-gate CMOS and 10,000-gate [[emitter coupled logic]] (ECL) chipsgate arrays for a boost in clock speed from 10 MHz to 25 MHz, and rated at 50 MFLOPS peak for double precision per CPU (100 MFLOPS peak for single precision). It was Convex's most successful product.

The '''C2''' was followed by the '''C3''' in 1991, being essentially similar to the C2 but with a faster clock and support for up to 8 CPUs implemented with low density GaAs FPGAs. Various configurations of the C3 were offered, with between 50 to 240 MFLOPS per CPU. However, the C3 and the Convex business model were overtaken by changes in the computer industry. The arrival of RISC Microprocessors meant that it was no longer possible to develop cost-effective high performance computing as a standalone small low-volume company. While the C3 was delivered late, which resulted in lost sales, it was still not going to be able to compete with commodity high-performance computing in the long run.