Journaling

Before writing actual data, a journaling file system logs the metadata, thus incurring an overhead penalty that slows write throughput.

One way of improving performance under JFS is to disable metadata logging by using the nointegrity mount option. Note that the enhanced performance is achieved at the expense of metadata integrity. Therefore, use this option with extreme caution because a system crash can make a file system mounted with this option unrecoverable.

In contrast to JFS, Enhanced JFS does not allow you to disable metadata logging. However, the implementation of journaling on Enhanced JFS makes it more suitable to handle metadata-intensive applications. Thus, the performance penalty is not as high under Enhanced JFS as it is under JFS.