Description
This video shows how separating pages according to their access frequency decreases write amplification. The HotCold FTL separates pages into partitions according to their temperature. It is used with traces in which each input write request is tagged by a temperature tag. The user specifies the number of partitions, P, and the highest temperature of pages that belong to each partition. Here, the Zipf workloads from the HotCold-1 and Greedy-Zipf videos is served by the HotCold FTL with five partitions, one for every two temperatures. For this trace, this granularity is fine enough to reduce the skew in the cold partitions, so that garbage collection within each partition behaves as with a uniform workload. Indeed, MinValid stabilizes at 10- 11 pages like in Greedy-Uniform.