US 7,257,595 B2 · Transactional file system

Abstract

A transactional file system performs multiple file system operations as part of a user-level transaction. An application specifies that operations should be handled as part of a transaction, and the application is given a file handle associated with the transaction context. Operations are managed consistent with transactional behavior and data isolation is provided with multiple versions of a file and by tracking copies of pages that have changed. Transactional readers do not receive changes to a file made by transactional writers, until the transactional writer commits the transaction and the reader reopens the file. Logging and recovery are also facilitated by logging page data separate from the main log, with a unique signature that enables the log to determine whether a page was fully flushed to disk prior to a system crash. Namespace isolation is also provided until a transaction commits via isolation directories.

Claims62

Dependent claims

A system for maintaining files on at least one computer system, comprising a processor and computer-readable storage media storing computer-executable instructions which are implemented by the processor and which include:

means for receiving a first request at a file system to perform a first file system operation thereon, the first request including data that indicates to the file system that the first request is associated with a transaction specified by a program;
means for performing the first file system operation;
means for maintaining information within the file system indicating that the first file system operation is associated with the transaction;
and
means for committing the first file system operation when the transaction commits.

2 more elements

In a computing environment, a system comprising a processor and computer-readable storage media storing computer-executable instructions which are implemented by the processor and which include:

means for receiving at a file system a first request corresponding to a first file and a requested operation to perform with respect to the first file, the first request associated with data that indicates to the file system that the first request is associated with a transaction;
means for recognizing at the file system that the first file is associated with the transaction;
means for receiving at the file system a second request corresponding to a second file and a requested operation to perform with respect to the second file, the second request associated with data that indicates to the file system that the second request is associated with the transaction that is also associated with the first file;
means for recognizing at the file system that the second file is associated with the transaction;
means for performing the requested operation to at least one of the first or second file;
and
means for undoing at the file system any successfully performed file system operations associated with the transaction when information is received that indicates that the transaction has aborted.

4 more elements

A computer-readable medium comprising one or more storage media storing computer-executable instructions, which when executed perform steps, comprising:

receiving a first request at a file system, the first request corresponding to a first file and a requested operation to perform with respect to the first file, the first request having data associated therewith that indicates that the first request is associated with a transaction;
recognizing at the file system that the first file is associated with a transaction;
performing the requested operation to the first file;
receiving a second request at the file system, the second request corresponding to a second file and a requested operation to perform with respect to the second file, the second request having data associated therewith that indicates that the second request is associated with a transaction;
recognizing at the file system that the second file is associated with the transaction that is also associated with the first file;
performing the requested operation to the second file;
receiving information at the file system regarding whether the transaction has successfully committed, and
if the transaction has successfully committed, committing the first and second file system operations, and
if the transaction has not successfully committed, undoing the first and second file system operations.

6 more elements

Dependencies are inferred from the claim text.

Transactional file system

Life of this patent

Transactional file system

Life of this patent

Abstract

Claims62