On Thu 26-08-10 10:25:47, Tejun Heo wrote:

On 08/25/2010 10:02 PM, Jan Kara wrote:

quoted

On Wed 25-08-10 17:57:41, Tejun Heo wrote:

quoted

On 08/25/2010 06:00 PM, Christoph Hellwig wrote:

quoted

On Wed, Aug 25, 2010 at 05:58:42PM +0200, Christoph Hellwig wrote:

quoted

On Wed, Aug 25, 2010 at 05:47:43PM +0200, Tejun Heo wrote:

quoted

From: Christoph Hellwig <hch@infradead.org>

ext4 already uses synchronous discards, no need to add I/O barriers.

This needs the patch that Jan sent in reply to my initial version merged
into it.

Actually the jbd2 patch needs it merged, but the point still stands.

Yeah, wasn't sure about that one.  Has anyone tested it?  I'll be
happy to merge it but I have no idea whether it's correct or not and
Jan didn't seem to have tested it so...  Jan, shall I merge the patch?

  I'm quite confident the patch is correct so you can merge it I think but
tomorrow I'll give it some crash testing together with the rest of your
patch set in KVM to be sure.

Patch included in the series before jbd2 conversion patch.

  An update: I've set up an ext4 barrier testing in KVM - run fsstress,
kill KVM at some random moment and check that the filesystem is consistent
(kvm is run in cache=writeback mode to simulate disk cache). About 70 runs
without journal_async_commit passed fine, now I'm running some tests with
the option enabled and the first few rounds passed OK as well.

									Honza
-- 
Jan Kara [off-list ref]
SUSE Labs, CR