Re: >16TB issues

[Valerie Aurora <vaurora@redhat.com>]

On Wed, Jul 22, 2009 at 03:27:24PM -0700, Justin Maggard wrote:
> On Tue, Jul 21, 2009 at 12:21 PM, Andreas Dilger<adilger@sun.com> wrote:
> >> I shouldn't need e2fsprogs to be compiled 64-bit as well, right?
> >> Currently I've got a 64-bit kernel with 32-bit userspace.
> >
> > Yes, that is a potential problem.
> 
> It looks like it certainly is a problem with current e2fsprogs "pu"
> branch.  My latest findings from basic testing (just mkfs.ext4, then
> e2fsck -fy, and -- if e2fsck modified the filesystem -- another e2fsck
> -fy) are as follows:
> 
> 1)  64-bit mke2fs + 64-bit e2fsck
> Appears to work fine.  No errors reported anywhere.
> 
> 2)  64-bit mke2fs + 32-bit e2fsck
> Also appears to work fine.  llverfs --partial looked okay, and e2fsck
> reported no errors.
> 
> 3)  32-bit mke2fs + 64-bit e2fsck
> Mkfs.ext4 must have done something wrong, but e2fsck was able to fix
> it up, and future e2fsck (32 or 64-bit) runs reported no issues.
> e2fsck output was:
> Block bitmap differences:  +(1063780365--1063780367)
> +(1063780381--1063780383) +(1063782048--1063782431)
> -(5359140864--5359173631)
> Running mkfs through valgrind doesn't show any obvious errors.
> 
> 4) 32-bit mke2fs + 32-bit e2fsck
> Same as (3), for the mkfs and the first e2fsck again reported fixing
> the same block bitmap differences.  But after the first e2fsck was
> complete, the second e2fsck run reported:
> e2fsck: Superblock invalid, trying backup blocks...
> Group descriptor 0 checksum is invalid.  Fix? yes
> Group descriptor 1 checksum is invalid.  Fix? yes
> ...
> Group descriptor 81774 checksum is invalid.  Fix? yes
> followed by tons of block bitmap differences.

Great, this is really helpful.  I've added it to my todo list.

-VAL