On Wed 09-11-11 17:28:20, Kazuya Mio wrote: > 2011/11/08 9:03, Jan Kara wrote: > > On Fri 28-10-11 14:34:31, Kazuya Mio wrote: > >> 2011/10/25 22:40, Jan Kara wrote: > >>> Please no. Generally this boils down to what do we do with dirty data > >>> when there's error in writing them out. Currently we just throw them away > >>> (e.g. in media error case) but I don't think that's a generally good thing > >>> because e.g. admin may want to copy the data to other working storage or > >>> so. So I think we should rather keep the data and provide a mechanism for > >>> userspace to ask kernel to get rid of the data (so that we don't eventually > >>> run OOM). > >> > >> I see. I agree with you. > >> > >>>> Do you have any ideas? > >>> So the question is what would you like to achieve. If you just want to > >>> unblock a thread then a solution would be to make a thread at > >>> balance_dirty_pages() killable. If generally you want to get rid of dirty > >>> memory, then I don't have a really good answer but throwing dirty data away > >>> seems like a bad answer to me. > >> > >> The problem is that we cannot unmount the corrupted filesystem due to > >> un-killable dd process. We must bring down the system to resume the service > >> with no dirty pages. I think it is important for the service continuity > >> to be able to kill the thread handling in balance_dirty_pages(). > > OK, attached are two patches based on latest Linus's tree that should > > make your task killable. Can you test them? > > I'm trying to reproduce now, but it's hard. Could you wait a few days? Sure, take as much time as you need. Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- 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
