Thanks. Unfortunately, this machine with this file system can boot only with 3.10 kernel somehow. Now it is started, and I hope it can hold the line while I'm creating another machine with a different FS. This is not a criticism towards BTRFS, this is a criticism to myself to not thinking enough before implementing this service
Thanks all for the help Laszlo > open_ctree errors with healthy but slow filesystems. > IIRC x-systemd.mount-timeout=infinity in fstab can be used to avoid > these errors. > > Best regards, > > Lionel