The idealdistributed file system wouldprovide all its userswith coherent,shared access tothe samesetoffiles,yetwould be arbitrarily scalable to provide more storage space and higher performance to a growing user community. It would be highly available in spite of component failures. It would require minimal human administration, and administration would not become more complex as more components were added. Frangipani is a new file system that approximates this ideal, yet was relatively easy to build because of its two-layer structure. The lower layer is Petal (described in an earlier paper), a distributed storage service that provides incrementally scalable, highly available, automatically managed virtual disks. In the upper layer, multiple machines run the same Frangipani file system code on top of a shared Petal virtual disk, using a distributed lock service to ensure coherence. Frangipaniis meantto run in a cluster of machinesthatare under a common administration and can commu...
Chandramohan A. Thekkath, Timothy Mann, Edward K.