> > Finally, I wonder if there should be some timeout of that wait. I > > don't know why, but I wouldn't be surprised if we hit some glitch which > > causes us to add one! > > > > If we hit such a situation it means that flush is no longer working which > is interesting in itself. I guess one possibility where it can occur is > if we hit global dirty limits (or memcg dirty limits when they exist) > and the page is backed by NFS that is disconnected. That would stall here > potentially forever but it's already the case that a system that hits its > dirty limits with a disconnected NFS is in trouble and a timeout here will > not do much to help. Agreed. I've run into such cases and cannot login even locally because the shell will be blocked trying to write even 1 byte at startup time. Any opened shells are also stalled on writing to .bash_history etc. Thanks, Fengguang -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>