P2FS: supporting atomic writes for reliable file system design in PCM storage

Abstract

This letter analyzes the characteristics of write operations in file systems for PCM (phase-change memory), and observes that a large proportion of writes only involve a small modification of the previous version. This observation motivates a new file system for PCM called P2FS, which reduces write traffic to PCM by exploiting the similarity of data between versions, while preserving the same reliability level of existing copy-on-write file systems. Experimental results show that P2FS reduces file I/O time by 48%, and energy consumption by 65%, on average, compared to copy-on-write.