rfc: [patch] change attribute for ext3

[Andreas Dilger]

On Sep 15, 2006  12:19 +0200, Alexandre Ratchov wrote:
> BTW, note that when we'll add support for nanosecond time-stamps, we still
> have the same problem, because with a very high clock and time-stamp
> resolutions, we'll have to update the inode on every change.

If we have a journal commit callback, then even if the in-core inode ctime
is changed continually, the on-disk inode will be updated exactly once per
jbd transaction.  The problem as it stands now is that the ext3/VFS code
doesn't know where a transaction boundary is, so it has to continually
update the on-disk inode to make sure that the changes are in the relevant
transaction.

I recall a long time ago that Andrew got significant improvement from
reducing the number of mark_inode_dirty() calls in ext3, just because of
avoiding the repeated core->disk inode packing.

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.