On Wed, 7 March 2007 09:51:35 +0100, Jan Kara wrote:

  I'll probably first write some userspace fs-reorganizer to find out how
much these changes in layout are able to give you in performance (i.e.
whether it's worth the effort of more complicated kernel online
defragmenter).

Have tried profiling the read accesses and prereading them
asynchronously on startup?  That appears to have improved E17 a lot.
See http://lca2007.linux.org.au/talk/101 (and watch the video).

Jörn

-- 
The competent programmer is fully aware of the strictly limited size of
his own skull; therefore he approaches the programming task in full
humility, and among other things he avoids clever tricks like the plague.
-- Edsger W. Dijkstra