Write Once, Get 50% Free: Saving SSD Erase Costs Using WOM Codes

Abstract: NAND flash is a write-once medium, where each memory cell must be erased prior to writing, and its lifetime is limited by the number of block erasures. A promising approach to eliminate erasures and extend the memory lifetime is to use WOM codes. However, these codes inflate the physically stored data and thus reduce the available capacity. We present Reusable SSD, in which invalid pages are reused for additional writes, without modifying the drive's exported storage capacity or page size.

Bio: Eitan Yaakobi is an Assistant Professor at the Computer Science Department at the Technion. He received the B.A. degrees in computer science and mathematics, and the M.Sc. degree in computer science from the Technion in 2005 and 2007, respectively, and the Ph.D. degree in electrical engineering from UCSD in 2011. Between 2011-2013, he was a postdoctoral researcher at Caltech. His research interests include information and coding theory with applications to non-volatile memories and data storage.