Improving Performance of a Distributed File System Using OSDs and Cooperative Cache

zFS is a scalable distributed file system that uses Object Store Devices (OSDs) for storage management and a set of cooperative machines for distributed file management. zFS evolved from the DSF project [7], and its high-level architecture is described in [11]. This work uses a cooperative cache algorithm, which is resilient to network delays and nodes failure. The work explores the effectiveness of this algorithm and of zFS as a file system. This is accomplished by comparing the system’s performance to NFS using the IOZONE[8] benchmark. We also investigate whether using a cooperative cache results in better performance, despite the fact that OSDs have their own caches. Our results show that the zFS prototype performs better than NFS when cooperative cache is activated and that zFS provides better performance even though the OSDs have caches of their own. We also demonstrate that using pre-fetching in zFS increases performance significantly. Thus, zFS performance scales well when the number of participating clients increases.