Patent ID: 8055702

Claim:
A network caching system, comprising: a caching computer having one or more network adapters to receive a data access request issued by a multi-protocol client and directed to a storage object cached by the caching computer, the storage object having data and attributes stored on an origin computer, the origin computer coupled to the caching computer; the caching computer having an operating system to organize a file system configured to manage a sparse volume that virtualizes a storage space provided by the origin computer to thereby provide storage virtualization of the storage object; the operating system having a fetch on demand (FOD) request sent from the caching computer to the origin computer in response to receipt of the data access request directed to the storage object, the FOD request requesting a latest copy of the attributes of the storage object, the FOD request sent without first determining if requested data of the storage object is cached in the caching computer; in response to receiving the latest copy of the attributes, the operating system of the caching computer to determine whether a change occurred in any of the attributes since the storage object was cached at the caching computer; if so, the operating system to trigger an ejection of the storage object cached on the caching computer; the operating system of the caching computer to further determine whether the data access request modifies data stored on a cache volume of the caching computer; and if so, the caching computer to convey the data access request to the origin computer before the data at the caching computer is modified, and the caching system to process the data access request at the origin computer.