On Tue, Jun 15, 2010 at 07:10:26AM -0400, Christoph Hellwig wrote: > On Tue, Jun 15, 2010 at 08:55:38PM +1000, Nick Piggin wrote: > > > > What I do in fsblock is to maintain a block-nr sorted tree of dirty > > blocks. This works nicely because fsblock dirty state is properly > > synchronized with page dirty state. So writeout can just walk this in > > order and it provides pretty optimal submission pattern of any > > interleavings of data and metadata. No need for buffer boundary or > > hacks like that. (needs some intelligence for delalloc, though). > > I think worrying about indirect blocks really doesn't matter much > these days. For one thing extent based filesystems have a lot less > of these, and second for a journaling filesystem we only need to log > modification to the indirect blocks and not actually write them back > in place during the sync. At least for XFS the actual writeback can > happen a lot later, as part of the ordered list of delwri buffers. That's true, more importantly I meant any interleavings of data from more than one file too. -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>