Single transaction technique for a journaling file system of a computer operating system

• US 6,021,414 A
• Filed: 12/28/1998
• Issued: 02/01/2000
• Est. Priority Date: 09/11/1995
• Status: Expired due to Term

• Current Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Fuller, Billy J.
• Primary Examiner(s): Fetting, Anton W.
• Assistant Examiner(s): Corrielus, Jean M.
• Application Number:
  US09/221,624
• Time in Patent Office: 400 Days
• Field of Search: 707/201, 707/8, 707/7, 707/200, 707/202, 395/182.13, 395/670
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 16/1815 Journaling file systems
• CPC Class Codes: Y10S 707/99937 Sorting
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A single transaction technique for a journaling file system of a computer operating system in which a single file system transaction is opened for accumulating a plurality of current synchronous file system operations. The plurality of current synchronous file system operations are then performed and the single file system transaction closed upon completion of the last of the file system operations. The single file system operation is then committed to a computer mass storage device in a single write operation without the necessity of committing each of the separate synchronous file system operations with individual writes to the storage device thereby significantly increasing overall system performance. The technique disclosed is of especial utility in conjunction with UNIX System V based or other journaling operating systems.

Claims

1. A method for writing data from a computer system to a mass storage device comprising the steps of:

implementing a journaling file system operating on the computer system, the journaling file system comprising a logging device and a master device;

processing in the operating system a plurality of file system operations using the computer system, wherein synchronous file system operations are generated by an external application program and refer to data stored at a specified location in the master device;

for each file system operation, providing an in-core copy of data from the master device;

for each file system operation, altering the in-core copy of data from the master device;

writing the altered in-core copy corresponding to each file system operation to the master device;

accumulating a plurality of the file system operations into a single logging transaction; and

performing the single logging transaction by writing the single logging transaction to the logging device.

2. The method of claim 1 wherein each synchronous file system operation comprises a file system operation generated by an external application in which all data must be committed before application program code can continue executing.

3. The method of claim 1 wherein each synchronous file system operation comprises an operation in which each operation is treated as a separate transaction, and wherein each synchronous file operation requires at least one write to the mass storage device per operation.

4. A computer program product comprising:

a propagating signal having computer readable code embodied therein for causing data to be written from a computer system to a mass storage device;

computer readable code segment in the propagating signal comprising code configured to implement a logging device in the mass storage device;

computer readable code segment in the propagating signal comprising code configured to implement a master device in the mass storage device;

computer readable code segment in the propagating signal comprising code configured to process a plurality of file system operations using the computer system, wherein the file system operations are generated by an external application program and refer to data stored at a specified location in the master device;

computer readable code segment in the propagating signal comprising code configured to provide an in-core copy of data from the master device for each file system operation;

computer readable code segment in the propagating signal comprising code configured to alter the in-core copy of data from the master device for each file system operation;

computer readable code segment in the propagating signal comprising code configured to write the altered in-core copy corresponding to each file system operation to the master device;

computer readable code segment in the propagating signal comprising code configured to accumulate a plurality of the file system operations into a single logging transaction; and

computer readable code segment in the propagating signal comprising code configured to perform the single logging transaction by writing the single logging transaction to the logging device.

5. The computer program product of claim 4 wherein the file system operations comprise synchronous file system operations.

6. A computer system having a processor and a memory operatively coupled to the processor, the computer system comprising:

a mass storage device coupled to the processor for receiving data, the mass storage device having a logging device and a master device;

an operating system executing on the processor, the operating system operatively coupled to application programs for performing a plurality of file system operations;

a journaling file system implemented within the operating system, the journaling file system coupled to write log transactions to the logging device and file system transactions to the master device; and

a transaction device within the journaling file system for creating a single log transaction for accumulating log records corresponding to a plurality of file system operations.

7. The computer system of claim 6 wherein the file system operations comprise synchronous file system operations.

8. The computer system of claim 6 wherein each file system transaction is associated with a log record, and each log transaction comprises one or more log records.