Reliable Power-efficient Microprocessors

by
Niti Madan

Advised by
Rajeev Balasubramonian

High energy particles such as- neutrons from cosmic rays and alpha particles in packaging material when pass through a semiconductor device, can generate electron-hole pairs. This causes enough charge to be deposited which can switch the state of a transistor. This leads to propagation of incorrect values for a short duration of time resulting in logical faults. Since these faults do not reflect a permanent hardware failure, these faults are known as soft errors or transient faults. These radiation-induced soft errors in computer systems have increased significantly over the last few years and are expected to increase even more as we move towards smaller transistor sizes and lower supply voltages. One of the most commonly adopted solutions to increase fault-coverage is to add redundancy by executing two copies of the same program either in two threads or in two separate processors and checking the results after every few cycles. The abovementioned approach is a good solution from the point of view of reliability but incurs a high power consumption penalty. The goal of this research project is to design power-efficient reliable microprocessors using novel micro-architectural techniques.