The proposed ASKS (Architecture Support for darK Silicon) project proposes architectural support for future many-core microprocessors designed with and around emerging technologies to address the challenges of the coming dark silicon revolution. Future many-cores, to stay on the historical performance curve, will contain more transistors than can all be sustainably powered at the same time. Thus, we face the prospect of ?dark silicon,? wherein some of a chip?s components must be powered-off (darkened) in order to stay within the chip?s power/thermal budget. Ensuring peak performance under these circumstances is a challenging task. In particular, in an architecture with different types of components (cores, caches, network on chip (NoC, or on-chip interconnet), memory controllers, etc.), there can be many different on-dim-dark configurations within the power budget. However, these can exhibit significantly varying performances. Additionally, the power consumption of uncore components (shared caches, on-chip interconnect, memory architecture) is significant, thus the uncore components play an important role in joint performance/power/thermal optimization. Therefore, a more inclusive approach is needed. Our architectural design space exploration will mainly focus on the uncore space (shared caches, on-chip interconnect structures, memory architecture), targeting future NoC-based many-core microprocessors that exploit the emerging technologies of 3D die-stacking (3D IC) and non-volatile memories (NVM).
This project will advance the state of the art in preparing for the dark silicon revolution in two main aspects. 1) Cross-layer holistic optimization with a focus on uncore components: The uncore components play important roles in joint performance/power/thermal optimization. This project proposes an integrated approach in which the cores and uncore components collaborate to maximize performance under power and thermal constraints as well as under dynamically changing program behavior and execution parameters. 2) Investigating dark silicon in the context of emerging technologies: Emerging 3D ICs and NVM technologies are envisioned as promising ways to design future many-core architectures. The adoption of such emerging technologies poses new challenges for dark silicon (such as aggravated thermal profiles in 3D stacked chips), but also brings new opportunities for architectural innovations such as novel power management techniques and greater exploitation of memory system heterogeneity. The broader impact of this project includes the contribution to the increased performance for future microprocessors even in the face of the coming dark silicon revolution. Through close collaboration with several industry partners, the PIs envision direct transfer of many ideas to industry. The tools and techniques developed in this project will be used in teaching existing courses and developing new courses, and will be made available through the web for use by other educators, researchers, and industry practitioners. Dissemination of research findings will also be carried out through conference tutorials, panel discussions, and workshops. A concerted effort will be made to involve under-represented groups and undergraduate students in this research.
