Improving Performance of Linux File System with Adaptive File Rearrangement

Abstract

Though computer devices are innovated continuously with the evolution of the technology, hard disk is still the bottleneck of the system performance. In this paper, we propose an adaptive file rearrangement mechanism to reduce disk seek times in accessing files to improve file system performance. Basically, frequently accessed files will be dynamically migrated to the space located at the center of the hard disk during the manipulation of disk files. Besides, we exploit application provided data access behavior to create hot files in the central disk. Furthermore, for the cost-effective concern, we also propose a method to reduce the file migration overhead. If the original disk location of a file to be migrated is close enough to the central disk, the file will not be migrated. We have implemented the proposed adaptive file rearrangement mechanism by modifying the Ext3 file system of Linux kernel 2.6. Experimental results show that our modified Ext3 file system can effectively decrease disk access time and improve file system performance.