In computer systems, the storage hierarchy, composed of a disk drive and a DRAM, is responsible for a large portion of the total energy consumed. This work studies the energy merit of interposing flash memory as a streaming buffer between the disk drive and the DRAM. Doing so, we extend the spin-off period of the disk drive and cut down on the DRAM capacity at the cost of (extra) flash. We study two different streaming applications: mobile multimedia players and media servers. Our simulated results show that for light workloads, a system with a flash as a buffer between the disk and the DRAM consumes up to 40% less energy than the same system without a flash buffer. For heavy workloads savings of at least 30% are possible. We also address the wear-out of flash and present a simple solution to extend its lifetime.
|Place of Publication||Enschede|
|Publisher||Distributed and Embedded Security (DIES)|
|Number of pages||15|
|Publication status||Published - 30 Jun 2007|
|Name||CTIT Technical Report Series|
|Publisher||Centre for Telematics and Information Technology, University of Twente|
Khatib, M. G., van der Zwaag, B. J., Hartel, P. H., & Smit, G. J. M. (2007). Interposing Flash between Disk and DRAM to Save Energy for Streaming Workloads. (CTIT Technical Report Series; No. P2773/TR-CTIT-07-43). Enschede: Distributed and Embedded Security (DIES).