On Sat, Dec 3, 2016 at 11:40 AM, Marc Joliet <mar...@gmx.de> wrote: > Hello all, > > I'm having some trouble with btrfs on a laptop, possibly due to qgroups. > Specifically, some file system activities (e.g., snapshot creation, > baloo_file_extractor from KDE Plasma) cause the system to hang for up to about > 40 minutes, maybe more.
Do you get any blocked tasks kernel messages? If so, issue sysrq+w during the hang, and then check the system log (dmesg may not contain everything if the command fills the message buffer). If it's a hang without any kernel messages, then issue sysrq+t. https://www.kernel.org/doc/Documentation/sysrq.txt > > After I next turned on the laptop, the balance resumed, causing bootup to > fail, after which I remembered about the skip_balance mount option, which I > tried in a rescue shell from an initramfs. The file system is the root filesystem? If so, skip_balance may not be happening soon enough. Use kernel parameter rootflags=skip_balance which will apply this mount option at the very first moment the file system is mounted during boot. > Since I couldn't use skip_balance, and logically can't destroy qgroups on a > read-only file system, I decided to wait for a regular mount to finish. That > has been running since Tuesday, and I am slowly growing impatient. Haha, no kidding! I think that's very patient. > Thus I arrive at my question(s): is there anything else I can try, short of > reformatting and restoring from backup? Can I use btrfs-check here, or any > other tool? Or...? Yes, btrfs-progs 4.8.5 has the latest qgroup checks, so if there's something wrong it should find it and if not that's a bug of its own. > Also, should I be able to avoid reformatting: how do I properly disable quota > support? 'btrfs quota disable' is the only command that applies to this and it requires rw mount; there's no 'noquota' mount option. -- Chris Murphy -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
