Hybrid Refresh: Improving DRAM Performance by Handling Weak Rows Smartly
Samiksha Verma, Shirshendu Das, Vipul Bondre · 2022
Modern memory systems use DRAM as their basic building block due to its low cost per bit property. DRAM cells are leaky and they need to be refreshed periodically to retain their data. Refresh operation degrades memory throughput by adding extra latency and eats up significant power. The refresh rate of the overall DRAM is decided according to the retention time of the weakest row. Although there are very few rows that need refresh at a high rate, it is kept same for all the rows as per the standard DRAM refresh technique. Many existing papers work on reducing refresh overhead, but they are compromising with space either by discarding weak rows or populating them with duplicate data.