Possible performance problem introduced between kernel 2.6.15 and 2.6.17 on xfs code

[fdegrassi <francesco.degrassi@xxxxxxxxx>]

Hi all,
i noticed that changing from kernel 2.6.15 to 2.6.17, gnomevfs-copy 
operations suffered an heavy performance hit (20 times slower).
I checked quickly (i am not a kernel hacker) and i think it could be 
related to libgnomevfs calling fadvice POSIX_FADV_DONTNEED  (in 
gnome_vfs_forget_cache, disabling this behaviour gets back normal 
performance).
I am not able to dig deeper than this, anyway it could be a starting point.
The relevant gnome bugzilla reference is the following: 
http://bugzilla.gnome.org/show_bug.cgi?id=363400
Francesco Degrassi