On Thu, Apr 21, 2011 at 03:14:26AM -0400, Christoph Hellwig wrote: > On Thu, Apr 21, 2011 at 05:09:47PM +1000, Dave Chinner wrote: > > Likely just timing. When IO completes and updates the inode IO size, > > XFS calls mark_inode_dirty() again to ensure that the metadata that > > was changed gets written out at a later point in time. > > Hence every single file that is created by the test will be marked > > dirty again after the first write has returned and disappeared. > > > > Why you see different numbers? it's timing dependent based on Io > > completion rates - if you have a fast disk the IO completion can > > occur before write_inode() is called and so the inode can be written > > and the dirty page state removed in the one writeback_single_inode() > > call... > > > > That's my initial guess without looking at it in any real detail, > > anyway. > > We shouldn't have I_DIRTY_PAGES set for that case, as we only redirty > metadata. But we're actually doing a xfs_mark_inode_dirty, which > dirties all of I_DIRTY, which includes I_DIRTY_PAGES. I guess it > should change to > > __mark_inode_dirty(inode, I_DIRTY_SYNC | I_DIRTY_DATASYNC); Probably should. Using xfs_mark_inode_dirty_sync() might be the best thing to do. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>