[20/20/Discussion] Memory Hierarchy: Caching is heavily used in some WSC designs to reduce latency, and there are multiple caching options to satisfy varying access patterns and requirements. a. [20]...

[20/20/Discussion] Memory Hierarchy: Caching is heavily used in some WSC designs to reduce latency, and there are multiple caching options to satisfy varying access patterns and requirements. a. [20] Let’s consider the design options for streaming rich media from the Web (e.g., Netflix). First we need to estimate the number of videos, number of encode formats per video, and concurrent viewing users. Assume a streaming video provider that has 12,000 titles for online streaming, each title having at least four encode formats (at 500, 1000, 1600, and 2200 kbps). Let’s also assume that there are 100,000 concurrent viewers for the entire site, and an average video is 75 min long (accounting for both 30-min shows and 2-h videos). Estimate the total storage capacity, I/O and network bandwidths, and video-streaming-related computation requirements. b. [20] What are the access patterns and reference locality characteristics per user, per video, and across all videos? (Hint: Random versus sequential, good versus poor temporal and spatial locality, relatively small versus large working set size.) c. [Discussion] What movie storage options exist by using DRAM, SSD, and hard drives? Compare them in performance and TCO. Would new memory technologies like those in Problem 6.17(d) be useful?