Transaction based virtual file system optimized for high-latency network connections

• US 7,908,339 B2
• Filed: 06/02/2005
• Issued: 03/15/2011
• Est. Priority Date: 06/03/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Maxsp Corporation
• Inventors: Keith, Jr., Robert O.
• Primary Examiner(s): Phillips, Hassan
• Assistant Examiner(s): LEE, BRYAN Y
• Application Number:
  US11/144,179
• Publication Number:
  US 20060047716A1
• Time in Patent Office: 2,112 Days
• Field of Search: 709/217
• US Class Current: 709/217
• CPC Class Codes: G06F 16/188 Virtual file systems

Abstract

A method and system are provided for a virtual distributed data manager. In one example of the method, the virtual data manager involves receiving a request to mount a file system onto the client computer, wherein the file system is stored on the server system and contains the one or more data files; transferring a copy of a directory structure of the file system stored on the server system to the client computer; and creating on the client computer a virtual file system including the copy of the directory structure. The method is preferably transaction based and provides high performance on high latency network connections.

Claims

1. A method of managing one or more data files over a network, wherein the network is configured to be connected to a server system and to a client computer, the method comprising:

receiving a request to mount a file system onto the client computer, wherein the file system is stored on the server system and contains the one or more data files;

transferring a copy of a directory structure of the file system stored on the server system to the client computer;

generating on the client computer a virtual file system including the copy of the directory structure, wherein the virtual file system is an individual user file system, and further wherein each of the one or more data files are not transferred from the server system to the client computer until individually requested;

receiving a request to open a data file of the one or more data files;

determining whether a client file version of the data file is available on the client computer;

determining that a client file version is available;

obtaining a Cyclic Redundancy Check value of a server file version of the data file;

obtaining a Cyclic Redundancy Check value of the client file version of the data file;

comparing the Cyclic Redundancy Check value of the server file version to the Cyclic Redundancy Check value of the client file version;

determining that the Cyclic Redundancy Check value of the server file version is unequal to the Cyclic Redundancy Check value of the client file version;

checking whether a Cyclic Redundancy Check value of another server file version is equal to the Cyclic Redundancy Check value of the client file version

determining that the Cyclic Redundancy Check value of the other server file version is equal to the Cyclic Redundancy Check value of the client file version;

generating a differential of the server file version;

transferring the differential to the client computer; and

merging the differential with the client file version to generate a current client file version matching the other server file version.

2. The method of claim 1, further comprising:

determining that the Cyclic Redundancy Check value of the server file version is equal to the Cyclic Redundancy Check value of the client file version; and

assigning an acceptable status to the request to open the data file.

3. The method of claim 1, further comprising:

determining that the Cyclic Redundancy Check value of the other server file version is unequal to the Cyclic Redundancy Check value of the client file version;

transferring a copy of the server file version to the client computer; and

synchronizing the client file version with the server file version.

4. The method of claim 1, further comprising:

determining that a client file version is unavailable; and

transferring a server file version of the data file from the server system to the client computer.

5. The method of claim 1, further comprising:

receiving a request to open a data file of the one or more data files;

checking for a valid network connection between the client computer and the server system;

determining that a valid network exists; and

updating the file system stored on the server system.

6. The method of claim 5, wherein updating the file system is performed asynchronously as a background operation.

7. The method of claim 1, wherein the request to mount the file system is received when a network connection between the client computer and the server system does not exist, the method further comprising:

displaying an error message; and

providing an option of at least one of waiting for the network connection or working on data files offline.

8. A server system for managing one or more data files over a network, wherein the network is configured to be connected to the server system and to a client computer, the server system comprising a file system including a directory having a directory structure and the one or more data files, wherein the server system is configured to receive a request to mount the file system onto the client computer, to transfer a copy of the directory structure to the client computer, and to instruct the client computer to generate a virtual file system including a copy of the directory structure, wherein the virtual file system is an individual user file system, and further wherein each of the one or more data files are not transferred from the server system to the client computer until individually requested, wherein the server system is further configured to receive a Cyclic Redundancy Check value of a client file version of a data file, to obtain a Cyclic Redundancy Check value of a server file version of the data file, and to compare the Cyclic Redundancy Check value of the server file version to the Cyclic Redundancy Check value of the client file version, and further wherein if it is determined that the Cyclic Redundancy Check value of the server file version is unequal to the Cyclic Redundancy Check value of the client file version, then checking whether a Cyclic Redundancy Check value of another server file version is equal to the Cyclic Redundancy Check value of the client file version, and if it is determined that the Cyclic Redundancy Check value of the other server file version is equal to the Cyclic Redundancy Check value of the client file version, then generating a differential of the server file version, transferring the differential to the client computer and merging the differential with the client file version to generate a current client file version matching the other server file version.

9. The server system of claim 8, wherein the server system is further configured to receive a request to update a data file, and to receive difference information from the client computer, wherein the difference information is based on a comparison of a client prior version of the data file to a client current version of the data file.

10. A client computer for managing one or more data files over a network, wherein the network is configured to be connected to the client computer and to the server system, wherein the server system includes a file system having a directory with directory structure, wherein the client computer is configured to receive a request to mount the file system onto the client computer, wherein the client computer is further configured to receive a copy of the directory of the file system, the client computer comprising a virtual file system including the copy of the directory structure of the file system, wherein the virtual file system is an individual user file system, and further wherein each of the one or more data files are not transferred from the server system to the client computer until individually requested, wherein the server system is further configured to receive a Cyclic Redundancy Check value of a client file version of a data file, to obtain a Cyclic Redundancy Check value of a server file version of the data file, and to compare the Cyclic Redundancy Check value of the server file version to the Cyclic Redundancy Check value of the client file version, and further wherein if it is determined that the Cyclic Redundancy Check value of the server file version is unequal to the Cyclic Redundancy Check value of the client file version, then checking whether a Cyclic Redundancy Check value of another server file version is equal to the Cyclic Redundancy Check value of the client file version, and if it is determined that the Cyclic Redundancy Check value of the other server file version is equal to the Cyclic Redundancy Check value of the client file version, then generating a differential of the server file version, transferring the differential to the client computer and merging the differential with the client file version to generate a current client file version matching the other server file version.

11. The client computer of claim 10, wherein the client computer is further configured to receive a request to open a data file, and to check whether a client file version of the data file is available on the client computer.

12. The client computer of claim 10, wherein the client computer is further configured to receive a request to update a data file, to compare a client prior version of the data file to a client current version of the data file, and to generate difference information based on the comparing of the client prior version to the client current version.

13. A non-transitory computer-readable medium carrying one or more instructions for managing one or more data files over a network, wherein the network is configured to be connected to a server system and to a client computer, wherein the one or more instructions, when executed by one or more processors, cause the one or more processors to perform the following:

receiving a request to mount a file system onto the client computer, wherein the file system is stored on the server system and contains the one or more data files;

transferring a copy of a directory, having a directory structure, of the file system stored on the server system to the client computer;

generating on the client computer a virtual file system including the copy of the directory structure, wherein the virtual file system is an individual user file system, and further wherein each of the one or more data files are not transferred from the server system to the client computer until individually requested;

receiving a request to open a data file of the one or more data files;

determining whether a client file version of the data file is available on the client computer;

determining that a client file version is available;

obtaining a Cyclic Redundancy Check value of a server file version of the data file;

obtaining a Cyclic Redundancy Check value of the client file version of the data file;

comparing the Cyclic Redundancy Check value of the server file version to the Cyclic Redundancy Check value of the client file version;

determining that the Cyclic Redundancy Check value of the server file version is unequal to the Cyclic Redundancy Check value of the client file version;

checking whether a Cyclic Redundancy Check value of another server file version is equal to the Cyclic Redundancy Check value of the client file version

determining that the Cyclic Redundancy Check value of the other server file version is equal to the Cyclic Redundancy Check value of the client file version;

generating a differential of the server file version;

transferring the differential to the client computer; and

merging the differential with the client file version to generate a current client file version matching the other server file version.