File System Fragmentation - Performance Implications

Performance Implications

File system fragmentation is projected to become more problematic with newer hardware due to the increasing disparity between sequential access speed and rotational latency (and to a lesser extent seek time), of consumer-grade hard disks, on which file systems are usually placed. Thus, fragmentation is an important problem in recent file system research and design. The containment of fragmentation not only depends on the on-disk format of the file system, but also heavily on its implementation.

In simple file system benchmarks, the fragmentation factor is often omitted, as realistic aging and fragmentation is difficult to model. Rather, for simplicity of comparison, file system benchmarks are often run on empty file systems, and unsurprisingly, the results may vary heavily from real-life access patterns.

File system fragmentation has less impact upon the performance of solid state drives, as there is no mechanical seek time involved like with rotating media, though additional non-sequential I/O operations impacts system performance, and many file system architectures consume additional internal resources when fragmentation is present.