TWO LEVEL ADDRESSING IN STORAGE CLUSTERS

摘要

Digital objects are stored and accessed within a fixed content storage cluster by using a page mapping table and a pages index. A stream is read from the cluster by using a portion of its unique identifier as a key into the page mapping table. The page mapping table indicates a node holding a pages index indicating where the stream is stored. A stream is written to the cluster by storing the stream on any suitable node and then updating a pages index stored within the cluster. The cluster recovers from a node failure by first replicating streams from the failed node and reallocating a page mapping table to create a new pages index. The remaining nodes send records of the unique identifiers corresponding to objects they hold to the new pages index. A node is added to the cluster by reallocating a page mapping table.