On Mon, 2009-01-26 at 19:46 -0600, Eric Sandeen wrote:
> > Maybe, the ext4 (like ext3 does) will support it by doing this:
> > tune2fs -O ^has_journal /dev/sda1
> > Is possible to disable journaling on XFS too?
> No, it's not right possible today. There used to be a sort of config
> option that disabled journaling ages ago, but it's gone now. Not sure
> it ever worked on Linux.
It never did - suffered from adding "never-tested" code paths
in critical areas at the top of the journalling layer in XFS.
Alot of the ordering of work, releasing of resources, etc in
metadata I/O depends on work being scheduled at log I/O
completion time, so if you remove the log entirely, it moves
several things around in ways that are tricky to get right.
Its much simpler to just create a ramdisk and house the journal
there, if you don't want the benefits of a journal (which might
sound attractive, right up to the point you actually need them).