Method for selectively disabling file system journaling during a specific operation.
Publication Date: 2010-Dec-03
The IP.com Prior Art Database
Method for selectively disabling file system journaling during a specific OS operation.
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Method for selectively disabling file system journaling during a specific operation .
File system Journaling is a common technique used by some physical file system to allow the file system to recover to a consistent meta data state after an unexpected crash or power outage. The file system will first write a Journal entry when changing file system meta data. This meta data may be a directory entry, file entry, or file allocation blocks. Since the meta data is written to the Journal a consistent file system state can be established on reboot using the Journal if the file system was mounted at the time of the crash. Without Journaling the file system must be repaired by walking the entire file system using an Operating System (OS) supplied command such as fsck. This fsck command thus checks the file system consistency and repairs the file system. The drawback to Journaling, is that for Journaling to work the Journal must first be written to persistent media for use in the event of a crash before new space within the filesystem can be allocated to a file. At some point the file system will write the director entry or allocation block meta data to the file system persistent media. Since the meta data is in the Journal the file system does not need to wait on a entry to be written to the file system persistent media. When a file system is mounted the Journal is checked to see if outstanding Journal entries exist. If a Journal entry exists on mount the Journal entry is flushed to the file system persistent media.
The proposed idea is to determine at file system mount time if Journaling can be selectively disabled based on the operations that will be performed on the file system during a predetermined processing period. One example of a predetermined processing period that does not need Journali...