Converting information into different formats

• US 7,747,594 B2
• Filed: 05/28/2004
• Issued: 06/29/2010
• Est. Priority Date: 09/21/1998
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Liu, Chao-Chia, Probert, David Bradley Jr.
• Primary Examiner(s): Vo; Tim T.
• Assistant Examiner(s): Dwivedi; Mahesh H
• Application Number:
  US10/856,656
• Publication Number:
  US 20040220982A1
• Time in Patent Office: 2,223 Days
• Field of Search: 707/10, 707/205, 707/100, 707/201, 707/203, 707/1, 707/2, 707/200
• US Class Current: 707/705
• CPC Class Codes: G06F 16/258 Data format conversion from or to a database
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

A software layer (filter driver) residing between software components or application programs running locally or on a client across a network and a persistent store of an operating system provides on-the-fly conversions of persistent information formats. The filter driver determines which format a program expects, and dynamically converts the information from its storage format to the format expected by the program. Conversion includes both data format conversion, and conversion of access semantics. Loadable conversion modules are provided for converting application specific formats due to the potential large number of such formats which can be encountered. The filter driver may change the format that information is stored in based on access history or other system requirements. The software components or application programs may be ignorant of the true storage format used by the system, and thus the filter driver can be used to give old versions of software access to information stored in newer formats.

Claims

1. A method of dynamically converting between file formats on a computer system with a filter driver, the method comprising the steps of:

monitoring a plurality of access requests for a plurality of files stored in a persistent storage system, wherein each of the plurality of files has an original file format;

generating statistics regarding dynamic conversion of the original file format into a different file format that the plurality of access requests for the plurality of files are requested;

if a predetermined threshold based on the statistics is reached for one of the plurality of files, determining if the original file format for the one of the plurality of files is a most efficient format;

if the original file format is the most efficient file format, continuing monitoring the plurality of access requests;

if the original file format is not the most efficient file format, converting the original file format into the most efficient file format; and

storing the one of the plurality of files to the persistent storage system in the most efficient file format.

2. The method according to claim 1 further comprising the step of:

estimating an overall cost of the dynamic conversion of the original file format into the different file format utilizing the statistics.

3. The method according to claim 2 wherein the estimating step further comprises the step of:

estimating the overall cost of dynamic conversion through measuring at least a one of;

a number of cpu cycles, a memory usage, an on-disk storage size, an access latency, and an other predetermined resource metric.

4. The method according to claim 1 wherein the converting step is performed during a period of time when system resources are being underutilized.

5. One or more computer storage media storing computer executable instructions that when executed by a processor perform a method of dynamically converting between file formats on a computer system with a filter driver, the method comprising the steps of:

monitoring a plurality of access requests for a plurality of files stored in a persistent storage system, wherein each of the plurality of files has an original file format;

generating statistics regarding dynamic conversion of the original file format into a different file format that the plurality of access requests for the plurality of files are requested;

if a predetermined threshold based on the statistics is reached for one of the plurality of files, determining if the original file format for the one of the plurality of files is a most efficient format;

if the original file format is the most efficient file format, continuing monitoring the plurality of access requests;

if the original file format is not the most efficient file format, converting the original file format into the most efficient file format; and

storing the one of the plurality of files to the persistent storage system in the most efficient file format.

6. The one or more computer storage media according to claim 5, wherein the method further comprises the step of:

estimating an overall cost of the dynamic conversion of the original file format into the different file format utilizing the statistics.

7. The one or more computer storage media according to claim 6, wherein the estimating step further comprises the step of:

estimating the overall cost of dynamic conversion through measuring at least a one of;

a number of cpu cycles, a memory usage, an on-disk storage size, an access latency, and an other predetermined resource metric.

8. The one or more computer storage media according to claim 5 wherein the converting step is performed during a period of time when system resources are being underutilized.

9. A computer system that dynamically converts between file formats on a computer system with a filter driver, the computer system comprising:

one or more process for executing computer executable instructions;

one or more computer storage media storing computer executable instructions that when executed perform a method comprising the steps of;

monitoring a plurality of access requests for a plurality of files stored in a persistent storage system, wherein each of the plurality of files has an original file format;

generating statistics regarding dynamic conversion of the original file format into a different file format that the plurality of access requests for the plurality of files are requested;

if a predetermined threshold based on the statistics is reached for one of the plurality of files, determining if the original file format for the one of the plurality of files is a most efficient format;

if the original file format is the most efficient file format, continuing monitoring the plurality of access requests;

if the original file format is not the most efficient file format, converting the original file format into the most efficient file format; and

storing the one of the plurality of files to the persistent storage system in the most efficient file format.

10. The system according to claim 9 wherein the one or more computer storage media further includes instructions that when executed cause the method to further comprise the step of

estimating an overall cost of the dynamic conversion of the original file format into the different file format utilizing the statistics.

11. The system according to claim 10 wherein the estimating step further comprises the step of:

estimating the overall cost of dynamic conversion through measuring at least a one of;

a number of cpu cycles, a memory usage, an on-disk storage size, an access latency, and an other predetermined resource metric.

12. The system according to claim 9 wherein the converting step is performed during a period of time when system resources are being underutilized.