Dark Silicon arises because per-transistor power has stopped scaling while transistor density continues to grow.  The result is the “utilization wall” that prevents processors from using all their transistors at once.  We (in collaboration with Dr. Michael Taylor) wrote one of the earliest peer-reviewed architecture papers to describe of the utilization wall and to propose specialization as an architectural solution.

To demonstrate the value of this approach, developed a prototype mobile application processor called GreenDroid that leverage “dark silicon” to dramatically reduce energy consumption in smartphones. GreenDroid will provide many specialized processors targeting key portions of the Android smartphone platform.

We built GreenDroid with a custom-built, fully-automated toolchain that generates energy-efficient “conservation cores” (C-Cores) from application source code. The resulting specialized circuits can deliver up to 18x increases in energy efficiency without sacrificing performance. C-cores also incorporate focused reconfigurability that allows them to adapt to small changes in the target application while still realizing efficiency gains.