Development update: Journaling
By Ted Pogue on Jan 25, 2008
We are forging ahead with development of the next SAM-QFS release. Although, I cannot make any promises about features (This is software development after all), I wanted to provide a peek at some of our feature development. I'll try to provide these updates on a regular basis. I hope you find these useful.
JournalingOne of the features we are working on is journaling. Some of the benefits of jounaling to QFS are reduced need for samfsck and increased metadata performance. While QFS has a consistency model that generally does not require an fsck, except to reclaim lost space and clean up orphan inodes, journaling will reduce the need for this type of clean up after a panic. The bigger benefit to QFS is the increase in metadata performance. Journaling can reduce the frequency of disk accesses required for metadata-intensive applications. This boosts the performance of QFS. In some preliminary tests, we have already seen a significant increase in performance on Shared QFS clients with journaling enabled on the metadata server. I'll try to report some real numbers as development progresses.
'til next time, Ted