Re: [PATCH, RFC] Delayed logging of file sizes

Lachlan McIlroy
2007-11-26T00:21:04Z

David Chinner wrote:
> On Fri, Nov 23, 2007 at 06:04:39PM +1100, Lachlan McIlroy wrote:
>> The easy solution is to log everything so that log replay doesn't need
>> to check if the on-disk version is newer - it can just replay the log.
>> But logging everything would cause too much log traffic so this patch
>> is a compromise and it logs a transaction before we flush an inode to
>> disk only if it has changes that have not yet been logged.
>
> The problem with this is that the inode will be marked dirty during the
> transaction, so we'll never be able to clean an inode if we issue a
> transaction during inode writeback.
>

Ah, yeah, good point. I wrote this patch back before that "dirty inode
on transaction" patch went in. For this transaction though the changes
to the inode have already been made (ie when we set i_update_core and
called mark_inode_dirty_sync()) so there is no need to dirty it in this
transaction. I'll keep digging. Thanks.