Transputer

The transputer is a series of pioneering microprocessors from the 1980s, intended for parallel computing. To support this, each transputer had its own integrated memory and serial communication links to exchange data with other transputers. They were designed and produced by Inmos, a semiconductor company based in Bristol, United Kingdom. For some time in the late 1980s, many considered the transputer to be the next great design for the future of computing. While the transputer did not achieve this expectation, the transputer architecture was highly influential in provoking new ideas in computer architecture, several of which have re-emerged in different forms in modern systems. In the early 1980s, conventional central processing units (CPUs) appeared to have reached a performance limit. Up to that time, manufacturing difficulties limited the amount of circuitry that could fit on a chip. Continued improvements in the fabrication process had largely removed this restriction. Within a decade, chips could hold more circuitry than the designers knew how to use. Traditional complex instruction set computer (CISC) designs were reaching a performance plateau, and it wasn't clear it could be overcome. It seemed that the only way forward was to increase the use of parallelism, the use of several CPUs that would work together to solve several tasks at the same time. This depended on such machines being able to run several tasks at once, a process termed multitasking. This had generally been too difficult for prior microprocessor designs to handle, but more recent designs were able to accomplish it effectively. It was clear that in the future, this would be a feature of all operating systems (OSs). A side effect of most multitasking design is that it often also allows the processes to be run on physically different CPUs, in which case it is termed multiprocessing. A low-cost CPU built for multiprocessing could allow the speed of a machine to be raised by adding more CPUs, potentially far more cheaply than by using one faster CPU design.