For a specific system i wanted maximum performance, so i tried of turning the journaling on my ext4 device.
It took me some time to find out how, so here is a small howto:
1. Unmount your EXT4 filesystem
2. tune2fs -O ^has_journal /dev/sdX
3. mount your filesystem again.
And voila! You have an ext4 filesystem without a journal.
Note: This works if you have a kernel newer then 2.6.28!