Model and validation of block cleaning cost for flash memory

Abstract

Flash memory is a storage medium that is becoming more and more popular. Though not yet fully embraced in traditional computing systems, Flash memory is prevalent in embedded systems, materialized as commodity appliances such as the digital camera and the MP3 player that we are enjoying in our everyday lives. The cost of block cleaning is an important factor that strongly influences Flash memory file system performance analogous to the seek time in disk storage based systems. We show that three performance parameters, namely, utilization, invalidity, and uniformity characteristics of Flash memory strongly effect this block cleaning cost and present a model for the block cleaning cost based on these parameters. We validate this model using synthetic workloads on commercial Flash memory products.