The dark side of silicon

How can we reduce the power consumption of computers? Scientists at EPFL are exploring “dark silicon”.

Computing eats up energy – and it’s not a trivial matter! All the datacenters in the USA put together use as much energy as all the households in Switzerland. We have reason to believe that this phenomenon will continue exponentially, in line with our growing needs. Among the teams at EPFL that are working to reduce the energy consumption of electronic chips, the Parallel Systems Architecture Laboratory (PARSA) is exploring a solution that could reduce it by a factor of 100!

Dark computing opens up new perspectives. The idea is this: chips composed of hundreds of cores, each with its own specialization. Instead of a single processor that does everything, there is an assembly of specialized circuits, in which only the cores being used are activated, and the others disactivated.

In current computing models, one existing paradigm anticipates this concept: graphic circuits, specialized in display-related tasks. They provide a good example of how dark computing will affect our futures. “In the near future, network, storage and research functions will have their own, dedicated circuits, integrated in a single chip”, explains Babak Falsafi, Director of PARSA.

The concept is especially interesting for servers. “A datacenter represents millions of dollars of investment. Optimising power consumption becomes a real economic challenge.”

The hardware installed in datacenters requires enormous data processing. For example, during a simple translation request via Google. “The procedure doesn’t depend on grammatical analysis, but rather on a comparison of thousands of existing translations; these are stored, compared and sorted according to a statistical method. The same is true of many services, and as a result basic data management will therefore use more and more resources.” Such a task, if assigned to a specialized circuit, would require rather less energy.

The work performed in Babak Falsafi’s laboratory is part of the Eurocloud server program. Begun in 2010, it is expected to produce new prototypes two years from now.

Author: Lionel Pousaz

Source: EPFL