i-MIRROR: A Software Managed Die-Stacked DRAM-Based Memory Subsystem

This paper presents an operating system managed diestacked DRAM called i-MIRROR that mirrors high locality pages from the off-chip DRAM. Optimizing the problems of reducing cache tag area, reducing transfer bandwidth and improving hit latency altogether while using the die-stacked DRAM as hardware cache is extremely challenging. In this paper, we show that performance and energy efficiency can be obtained by software management of the die-stacked DRAM, which eliminates the need for tags, the source of aforementioned problems. In the proposed scheme, the operating system loads pages from disks to the die-stacked DRAM on a page fault at the same time as they are loaded to the off-chip DRAM. Our scheme maintains the pages in the off-chip and the die-stacked DRAM in a synchronized/mirrored state by exploiting the parallel loading capability to the die-stacked and off-chip DRAM from the disk. This eliminates the need for physical page movement to the slower off-chip DRAM upon eviction fro...

• Type: Journal
• Year: 2015
• Where: SBACPAD
• Authors: Jee Ho Ryoo, Karthik Ganesan, Yao-Min Chen, Lizy Kurian John
• Keywords: Hardware, SBACPAD 2015