Chunk retention in a distributed object storage system using stream sessions and stream session backreferences

摘要

The present disclosure provides an advantageous systems and related methods for scalable object storage. In accordance with an embodiment of the invention, a stream session is opened to initiate a retention epoch during which a series of edits to an object by a source may be performed without seeing edits from other stream sessions. Backreferences identifying the stream session (i.e. stream session backreferences) are applied to retained chunks. While a payload chunk has one or more such associated stream session backreferences, the chunk is retained and not expunged. Advantageously, transitory chunks that are put during the retention epoch may be unput promptly so as to release valuable cache resources. In comparison, the prior approach only eventually releases the data storage resources for expunged version manifests. Other embodiments, aspects and features are also disclosed.