Title
Zombie memory: extending memory lifetime by reviving dead blocks
Abstract
Zombie is an endurance management framework that enables a variety of error correction mechanisms to extend the lifetimes of memories that suffer from bit failures caused by wearout, such as phase-change memory (PCM). Zombie supports both single-level cell (SLC) and multi-level cell (MLC) variants. It extends the lifetime of blocks in working memory pages (primary blocks) by pairing them with spare blocks, i.e., working blocks in pages that have been disabled due to exhaustion of a single block's error correction resources, which would be 'dead' otherwise. Spare blocks adaptively provide error correction resources to primary blocks as failures accumulate over time. This reduces the waste caused by early block failures, making working blocks in discarded pages a useful resource. Even though we use PCM as the target technology, Zombie applies to any memory technology that suffers stuck-at cell failures. This paper describes the Zombie framework, a combination of two new error correction mechanisms (ZombieXOR for SLC and ZombieMLC for MLC) and the extension of two previously proposed SLC mechanisms (ZombieECP and ZombieERC). The result is a 58% to 92% improvement in endurance for Zombie SLC memory and an even more impressive 11x to 17x improvement for ZombieMLC, both with performance overheads of only 0.1% when memories using prior error correction mechanisms reach end of life.
Year
DOI
Venue
2013
10.1145/2485922.2485961
ISCA
Keywords
Field
DocType
error correction mechanism,memory page,slc mechanism,prior error correction mechanism,memory technology,memory lifetime,error correction resource,spare block,new error correction mechanism,primary block,zombie slc memory,zombie memory,dead block,error correction,phase change memory
Phase-change memory,Spare part,Computer science,Parallel computing,Working memory,Zombie,Error detection and correction,Real-time computing
Conference
Volume
Issue
ISSN
41
3
0163-5964
Citations 
PageRank 
References 
26
0.91
21
Authors
6
Name
Order
Citations
PageRank
Rodolfo Azevedo127130.84
John D. Davis2111054.37
Karin Strauss3111172.82
Parikshit Gopalan4118661.52
Mark Manasse51698177.12
Sergey Yekhanin698352.33