Erasure coding and replication in storage clusters

摘要

A cluster receives a request to store an object using replication or erasure coding. The cluster writes the object using erasure coding. A manifest is written that includes an indication of erasure coding and a unique identifier for each segment. The cluster returns a unique identifier of the manifest. The cluster receives a request from a client that includes a unique identifier. The cluster determines whether the object has been stored using replication or erasure coding. If using erasure coding, the method reads a manifest. The method identifies segments within the cluster using unique segment identifiers of the manifest. Using these unique segment identifiers, the method reconstructs the object. A persistent storage area of another disk is scanned to find a unique identifier of a failed disk. If using erasure coding, a missing segment previously stored on the disk is identified. The method locates other segments. Missing segments are regenerated.

主权项

1. A method of storing a digital object in a storage cluster, said method comprising:
receiving a request at a computer node of said storage cluster to store said digital object; determining whether to store said digital object in said storage cluster using replication or erasure coding; when it is determined to store said digital object using erasure coding, writing said digital object to a plurality of computer nodes of said storage cluster using erasure coding, said digital object being stored as a plurality of segments; creating a manifest computer file that includes a unique identifier within said storage cluster for each of said segments; and storing said manifest computer file on a computer node of said storage cluster.