Messages in this thread | | | Subject | Re: Filesystem optimization.. | Date | Tue, 06 Jan 1998 18:30:21 -0800 | From | Craig Milo Rogers <> |
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>When doing a path lookup, the directory must already have been >read. Embedding the inode has the neat advantage that reading the >directory automatically pulls the inode in at a very low cost.
Maybe, maybe not. If the directory entry you seek is not at the beginning of the directory, you may have to read more directory blocks from disk (proportional to the increased size of the enhanced directory entry) to reach the one you want.
If the enhanced directory blocks are cached and the pre-enhancement inode blocks wouldn't have been cached... that's probably a reasonable I/O improvement. If the enhanced directory blocks are not cached, and are not allocated consecutively and read-ahead... this could be a performance penalty.
What it boils down to, I think, is that someone needs to implement this idea so it can be tested in real systems. The result of the tests will determine whether the time spend implementing it was worthwhile. :-)
Craig Milo Rogers
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