Hello,

I'm currently experiencing high load on my linode caused by the kjournald process. I want to upgrade to the ext4 filesystem so that I can stop journalling.

I'm quite new to linux and not overly familiar with the mounting options.

I'm running Ubuntu 12.04.3 64-bit.

Is anyone able to confirm the following is the correct process? :

# sudo nano /etc/fstab

- change EXT3 to EXT4
- reboot the system

# tune2fs -o journal_data_writeback /dev/xvda
# sudo tune2fs -O extents,uninit_bg,dir_index /dev/xvda
# tune2fs -O ^has_journal /dev/xvda
# e2fsck -fDC0 /dev/xvda

- reboot the system
- configure options in /etc/fstab

Any help would be greatly appreciated.

Regards,
Paul

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My Website: http://www.paulthomson.me

If your only goal is to disable journaling, why not just do that part? Not certain this requires converting to ext4.

If you do decide to convert to ext4 anyway, you should be aware that the Linode Manager may not be able to resize disks that were originally created as ext3 and then converted to ext4. You may want to take this into consideration. It might be a better idea to create a raw disk, create an ext4 filesystem on the raw disk, tune2fs it, then move your stuff from the old ext3 disk to the new ext4 disk. At least you'll be able to grow such a disk later (you still wouldn't be able to shrink it though).

Thanks for the reply. From the research I've done there doesn't seem to be a way to disable journaling on ext3 (unless you know of one?).

The response from Linode staff:


Thanks for your recommendation on creating a ext4 filesystem on the raw disk and tune2fs-ing it. I've created a raw disk image from the linode dashboard, what would be the easiest way to copy the data across to it?

Thanks,
Paul

_________________
My Website: http://www.paulthomson.me

I can confirm that the steps I posted earlier work perfectly and successfully change the filesystem to ext3 to ext4. I've disabled the journalling and now don't experience any IO spikes - figured this would be helpful for some people out there.

Thanks for your help,
Paul

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My Website: http://www.paulthomson.me

You... do know what journalling is, right? Why do you have a grudge against your data?


As ext3 is simply ext2 with a journal, I believe you can just mount the fs as ext2. I don't think "tune2fs -O ^has_journal" is even necessary.

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Matt Nordhoff (aka Peng on IRC)

Running without journaling is a Bad Idea(tm). It makes data loss enormously more likely. If journaling is causing that much load, to me it would indicate some other problem...

Turns out it was a cache folder who's contents was being replaced far too often causing the journalling system to go nuts trying to keep up. My bad. Thanks for the input though.

_________________
My Website: http://www.paulthomson.me