On 12/02/2014 02:58 PM, Jan Kara wrote: > On Fri 28-11-14 13:14:21, Ted Tso wrote: >> On Fri, Nov 28, 2014 at 06:23:23PM +0100, Jan Kara wrote: >>> Hum, when someone calls fsync() for an inode, you likely want to sync >>> timestamps to disk even if everything else is clean. I think that doing >>> what you did in last version: >>> dirty = inode->i_state & I_DIRTY_INODE; >>> inode->i_state &= ~I_DIRTY_INODE; >>> spin_unlock(&inode->i_lock); >>> if (dirty & I_DIRTY_TIME) >>> mark_inode_dirty_sync(inode); >>> looks better to me. IMO when someone calls __writeback_single_inode() we >>> should write whatever we have... >> >> Yes, but we also have to distinguish between what happens on an >> fsync() versus what happens on a periodic writeback if I_DIRTY_PAGES >> (but not I_DIRTY_SYNC or I_DIRTY_DATASYNC) is set. So there is a >> check in the fsync() code path to handle the concern you raised above. > Ah, this is the thing you have been likely talking about but which I was > constantly missing in my thoughts. You don't want to write times when inode > has only dirty pages and timestamps - This I do not understand. I thought that I_DIRTY_TIME, and the all lazytime mount option, is only for atime. So if there are dirty pages then there are also m/ctime that changed and surly we want to write these times to disk ASAP. if we are lazytime also with m/ctime then I think I would like an option for only atime lazy. because m/ctime is cardinal to some operations even though I might want atime lazy. Sorry for the slowness, I'm probably missing something Thanks Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
