Processing-in-Memory Accelerator for Dynamic Neural Network with Run-Time Tuning of Accuracy, Power and Latency

With the widely deployment of powerful deep neural network (DNN) into smart, but resource limited IoT devices, many prior works have been proposed to compress DNN in a hardware-aware manner to reduce the computing complexity, while maintaining accuracy, such as weight quantization, pruning, convolution decomposition, etc. However, in typical DNN compression methods, a smaller, but fixed, network structure is generated from a relative large background model for resource limited hardware accelerator deployment. However, such optimization lacks the ability to tune its structure on-the-fly to best fit for a dynamic computing hardware resource allocation and workloads. In this paper, we mainly review two of our prior works [1], [2] to address this issue, discussing how to construct a dynamic DNN structure through either uniform or non-uniform channel selection based sub-network sampling. The constructed dynamic DNN could tune its computing path to involve different number of channels, thus providing the ability to trade-off between speed, power and accuracy on-the-fly after model deployment. Correspondingly, an emerging Spin-Orbit Torque Magnetic Random-Access-Memory (SOT-MRAM) based Processing-In-Memory (PIM) accelerator will also be discussed for such dynamic neural network structure.