SEQUENTIAL WRITE BASED DURABLE FILE SYSTEM

摘要

A durable file system has been designed for storage devices that do not support write in place and/or that are susceptible to errors or failures. The durable file system also facilitates organization and access of large objects (e.g., gigabytes to terabytes in size). Regardless of whether target storage devices are configured with sequential write constraints, the durable file system writes object fragments across a set of sequences or ranges of storage units, such as logical blocks. The durable file system sequentially writes an object fragment into each storage unit sequence along with indexing information for the object fragments. In addition to writing the indexing information for the object fragments into the set of storage unit sequences, the durable file system updates the file system index with the object indexing information.

主权项

1. A method comprising:
generating a plurality of fragments from an object after receipt of a request to write the object, which is identified by a client defined object identifier, into a file system instance; creating indexing information for the object that identifies the object, that identifies a set of storage unit sequences across a plurality of storage devices, and that indicates a same offset into each of the set of storage unit sequences; writing each of the plurality of fragments into a different one of the set of storage unit sequences and the created indexing information into each storage unit sequence of the set of storage unit sequences; after the plurality of fragments and the indexing information have been written into the set of storage unit sequences, updating an index of the file system instance with the indexing information.