On 12.09.19 г. 7:38 ч., David Newall wrote: > On 11/9/19 8:22 pm, Nikolay Borisov wrote: >>> I saved it tohttps://davidnewall.com/kern.1 >> Nothing useful in that log, everything seems normal. > > Thank you, again, for your help. I am grateful. > > If I understand the output, both df and mount are waiting for > show_mountinfo which is waiting for btrfs_show_devname which is waiting > to get a lock. They have to wait to find the devname for ten minutes. > Is that really normal? It's normal for them to wait for the lock, it's not normal for the lock to be taken for 10 minutes. > > I'm not saying that btrfs is behind it, but it does seem like something > is not right. >From my POV what's wrong is the fact that btrfs transaction commit is taking a long time. Is it possible that the underlying storage is exhibiting problems e.g. a dying disk/ssd? > > I notice that there's a waiting btrfs-transation, too. I don't know > what the transaction would be, and no doubt it's completely appropriate, > even though the use of btrfs at that point is merely one mount (and one > mount of ext2 over a sub-directory, probably no involvement by btrfs.) > > I see, too, that systemd is waiting for btrfs_show_devname. It's a > pattern. > > I take your point about the kernel being somewhat old and accept that > I'm unlikely to get far without confirming the problem on a recent kernel. > >
