On Thu, 10 Mar 2011 08:51:48 +1100 Dave Chinner <[email protected]> wrote: > > Sounds like a case for the same dirty page lifecycle as NFS: clean > -> dirty -> writeback -> unstable -> clean. i.e. the page is > unstable after the issuing of the IO until the response from the > server so the page can't be reclaimed while the IO is still in > progress at the server... >
It's a little more complicated than that for NFS. Unstable pages are ones that have had successful writes but that have not been committed yet. Once a NFS COMMIT call completes, the page is marked clean and can be freed by the VM. Actual writeback in NFS is pretty similar to other filesystems -- the page is only under writeback until the WRITE response is received. It just doesn't clear the dirty bit until a COMMIT response is received. That said, an unstable write model for CIFS is not a bad idea. Just substitute a SMB_COM_FLUSH for a NFS COMMIT call... -- Jeff Layton <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
