Emerging memory technologies such as STT-RAM, PCRAM, and resistive RAM are being explored as potential replacements to existing on-chip caches or main memories for future multi-core architectures. This is due to the many attractive features these memory technologies posses: high density, low leakage, and non-volatility. However, the latency and energy overhead associated with the write operations of these emerging memories has become a major obstacle in their adoption. Previous works have proposed various circuit and architectural level solutions to mitigate the write overhead. In this paper, we study the integration of STT-RAM in a 3D multi-core environment and propose solutions at the on-chip network level to circumvent the write overhead problem in the cache architecture with STT-RAM technology. Our scheme is based on the observation that instead of staggering requests to a write-busy STT-RAM bank, the network should schedule requests to other idle cache banks for effectively hidin...
Asit K. Mishra, Xiangyu Dong, Guangyu Sun, Yuan Xi