File System Logging Versus Clustering: A Performance Comparison
Margo Seltzer, Keith A. Smith, Hari Balakrishnan, Jacqueline A. Chang, Sara McMains, Venkata N. Padmanabhan · 1995
The Log-structured File System (LFS), introduced in 1991 [8], has received much attention for its potential order-of-magnitude improvement in file system performance. Early research results [9] showed that small file performance could scale with processor speed and that cleaning costs could be kept low, allowing LFS to write at an effective bandwidth of 62 to 83% of the maximum. Later work showed that the presence of synchronous disk operations could degrade performance by as much as 62% and that cleaning overhead could become prohibitive in transaction processing workloads, reducing performance by as much as 40% [10]. The same work showed that the addition of clustered reads and writes in the Berkeley Fast File System [6] (FFS) made it competitive with LFS in large-file handling and software development environments as approximated by the Andrew benchmark [4]. These seemingly inconsistent results have caused confusion in the file system research community. This paper presents a detail...