On Sun, 2009-11-08 at 16:03 +0100, Lennart Poettering wrote: > On Fri, 06.11.09 20:22, Alexander Larsson (al...@redhat.com) wrote: > > > There is one problem with POSIX_FADV_DONTNEED. If you do it on a file > > the kernel will drop it from its caches. This is generally what you want > > if you just indexed a 100 meg text file that no other app cares about > > atm, since it means we won't throw out 100 megs of otherwise useful > > caches. However, if you're reading a file that some other app actually > > cares about this may be a problem, since you're now ensuring that the > > file has to be re-read the next time that app wants to use the file. Not > > sure if there is a better way though... > > Shoudln't MADV_SEQUENTIAL do this? Enables aggressive read-ahead and > quick freeing according to the man page. Not sure though if the latter > is actually implemented by the VM in the way we'd want it here.
I don't see anything in SEQUENTIAL mentioning that you don't want the file cached. It seems to be mainly about readahead. This seems like what you'd really want: POSIX_FADV_NOREUSE The specified data will be accessed only once. However, its useless: In kernels before 2.6.18, POSIX_FADV_NOREUSE had the same semantics as POSIX_FADV_WILLNEED. This was probably a bug; since kernel 2.6.18, this flag is a no-op. _______________________________________________ desktop-devel-list mailing list desktop-devel-list@gnome.org http://mail.gnome.org/mailman/listinfo/desktop-devel-list