Persistent caching directory level support

• US 20050160096A1
• Filed: 02/22/2005
• Published: 07/21/2005
• Est. Priority Date: 10/23/2003
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Lin, Yun, Virk, Navjot, Aust, Brian S., Steere, David C., Pardikar, Shishir P., Samji, Mohammed A.
• Granted Patent: US 7,702,745 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching

Abstract

The present invention provides a novel client side caching (CSC) infrastructure that supports transition states at the directory level to facilitate a seamless operation across connectivity states between client and remote server. More specifically, persistent caching is performed to safeguard the user (e.g., client) and/or the client applications across connectivity interruptions and/or bandwidth changes. This is accomplished in part by caching to a client data store the desirable file(s) together with the appropriate file access parameters. Moreover, the client maintains access to cached files during periods of disconnect. Furthermore, portions of a path can be offline while other portions upstream can remain online. CSC operates on the logical path which cooperates with DFS which operates on the physical path to keep track of files cached, accessed and changes in the directories. In addition, truth on the client is facilitated whether or not a conflict of file copies exists.

Claims

1. An API that facilitates satisfying a create request on an online remote file system comprising:

receive the create request from I/O manager;

call a pre-process handler of a CSC surrogate provider;

find or create a logical namespace structure if part of the logical namespace on which a target of the create request resides is already offline;

pass the create request to a DFS surrogate provider to translate the logical path to an physical server share;

pass the create request to a redirector component to allow a redirector to claim the physical path; and

call a post-process handler of the CSC surrogate provider to express one of either no interest or interest to cache a file object requested by the create request.

2. An API that facilitates satisfying a create request on a client computer when disconnected from a remote file system comprising:

receive the create request from I/O manager; and

call a pre-process handler of a CSC surrogate provider to handle the request by mapping the logical path to local cache data since redirectors are unavailable to claim the path.