[OpenAFS] cache performance

[Nickolai Zeldovich]

> What do you think about using the mount options "noatime,data=writeback" 
> when using an ext3 filesystem for the AFS cache on linux systems.
> I think this could increase the performance on a heavily used cache.

The "noatime" option will not make any difference -- the kernel module
already sets the NOATIME bit on all the cache file inodes.  I don't know
for sure what the "data=writeback" option does, but guessing that it makes
the buffer cache a write-back one, sure, it may increase your performance.
Though I had the impression that Linux already did writeback caching..  Or
maybe that was only for ext2, and ext3 enforces more traditional semantics?

-- kolya