Moving /home partition to ext4

Yalla-One · 09-04-2009, 03:49 AM

With the upgrade to 64bit Slackware 13 I thought it might be time to upgrade the /home partition to ext4 as well. It's been the same for a couple of years and could probably use a "defrag" so rather than just upgrade the journal++ from ext3 to ext4, I wish to do a complete backup, reformat and restore.

From way back I remember various ext4-related questions to a change in default parameters to ext4 both at creation time and at mount time to prevent dataloss in case of a system crash. I can however not remember which way the default changed, and Google gives too many contradictary hits to make sense.

So here goes:

Are there any special parameters that I should add to mke2fs to make the new /home ext4 partition more robust?

Are there any matching parameters to be added to fstab?

Thanks in advance!

-y1

fusion1275 · 09-04-2009, 05:19 AM

You should take a look at my little help guide I created.

Quote:

http://www.linuxquestions.org/questi...l-disk-748095/

It should explain using LVM to creating a filesystem. Its very simple to do.

Hope this helps you.

Yalla-One · 09-04-2009, 05:29 AM

Hi,

Can't see any references to ext4 fs tuning in there anywhere, so i cannot see how that helps.

lvm is not needed for this setup. just looking for recommendations for fs blocksize and things like data written ordered,writeback or journaled etc...

gegechris99 · 09-04-2009, 06:19 AM

Maybe this Ext4_Howto could be helpful

tommcd · 09-04-2009, 06:28 AM

Here is another good tutorial on ext4:
http://wiki.archlinux.org/index.php/Ext4
It explains that you can mount your existing ext3 partition as ext4 for slightly improved performance. It also describes how to convert an ext3 partition to ext4.

I have read that if you are concerned about possible data corruption in the event of a system crash due to the delayed allocation feature of ext4, you can add nodelalloc to the partition's boot options in fstab. Although I have read that this is not really necessary with the most recent linux kernels that have better implementations of ext4.

Ilgar · 09-04-2009, 01:20 PM

In addition to the point that Tom made, remember that (as part of efforts to fix some I/O wait time regressions) the recent kernels (>= 2.6.30 I think) have a different default ext3 behaviour as well. You can see an earlier post of mine about this:

https://www.linuxquestions.org/quest...ml#post3569439

AFAIK 2.6.31 will include another new mount option which will improve the performance without raising data security concerns.