[Lustre-discuss] 8TB Lun Limit

[Andreas Dilger]

On Nov 26, 2007  11:08 -0500, Aaron Knister wrote:
> Is the 8TB lun size limit going to be lifted any time soon? Because of  
> this limit I'm only getting 33TB out of 45TB raw using raid5 with  
> terabyte drives. What is everybody else doing for large arrays over 8TB?

There will be no 8TB limit for new ZFS-based filesystems, available when
Lustre 1.8 ships (planned for July '08).

For ext3 filesystems, the 8TB limit will be removed once the upstream
kernel also removes this limit.  For RHEL5 I believe they are working
on up to 16TB per ext3 filesystem, but it isn't done yet, nor have we
tested it.  For ext4 based file system code (available from about Linux
2.6.22 and on) the 8TB limit was also removed, but we need to port our
ldiskfs patches over to be ext4 based.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.