Mounting ext3 with data=writeback for root partition?

[mdpye]

I have moved to ext3 and would like to use data=writeback on my root filesystem for better performance, but as it is mounted data=ordered by the kernel at boot up and you can't change the mode on remount, just putting data=writeback in /etc/fstab is not going to work.

How can I pass mount options to the kernel? I've tried appending a few likely looking strings using lilo, but no joy so far. Can anyone help?
_________________
Cheers, MP

[mdpye]

Found it:

rootflags=data=writeback

passed to the kernel is what I needed.
_________________
Cheers, MP

[BradN]

Cool! I was actually looking for that too.

[mdpye]

With most people using gentoo on their desktop machines, I'm sure writeback would be the most popular journal type for ext3, as it offers the same level of protection as reiserfs and xfs, so I think I'll drop a note at bugs.gentoo.org to have it included in the documentation.

For now I'll drop it in hints and tips...
_________________
Cheers, MP

[swingarm]

Newbie type question.
Do I put that under the opts category for the partition I want to use it on? For example:

/dev/sda3 / noatime,rootflags=data=writeback


Thanks,
Kent

[mdpye]

Only if that partition is not your root partition, and then it would read

/dev/sda3 /home ext3 noatime,data=writeback 0 0

For your root ("/") partition, the one shown below you must use your boot loader to pass the option to the kernel. Now I am an old lilo fan, and I have no experience with grub, but I add

append = "rootflags=data=writeback"

to my kernel image in /etc/lilo.conf.

...googling...

OK, the Gentoo FAQ suggests that to pass options to the kernel with grub, you can simply write than after the kernel image, so the line will look something like

kernel /boot/bzImage rootflags=data=writeback

Hope that helps.
_________________
Cheers, MP

[CoronaLover]

10x 10x 10x

[mdpye]