View Full Version : Can stride be removed from ext4?

2nd September 2011, 07:54 PM
Hi. This is a repost of a question I posted on another forum. couldn't get an answer on that one.

So I'm playing around with a LVM over RAID0 setup using mdadm. I created a throw-away ext4 filesystem, pvmoved it to the RAID0, then tuned it with a stride size of 8. (My rationale was that I had chosen a 32k chunk size, and 32/4 = 8. Not rocket science by any means.) However, before I start moving filesystems I care about onto the PV that is sitting on the RAID0 and permanently changing their attributes, I want to know that I can move them back. That means I want to be able to tell the filesystem that it no longer needs a stride. But try as I might, I've not been able to remove the stride extended option from the filesystem. I've tried several commands, including:

sudo tune2fs -E stride=0 /dev/notimportantforexample
tune2fs 1.41.12 (17-May-2010)
Invalid RAID stride: 0

Bad options specified.

Extended options are separated by commas, and may take an argument which
is set off by an equals ('=') sign.

Valid extended options are:
stride=<RAID per-disk chunk size in blocks>
stripe_width=<RAID stride*data disks in blocks>
hash_alg=<hash algorithm>

Is it even possible to remove this extended option from a filesystem?

Thanks in advance.