[Lustre-discuss] Maximum size of an OST

[Andreas Dilger]

On Jul 17, 2008  09:13 -0400, Wallior, Julien wrote:
> We are using lustre 1.6.4.3 and have 32bit clients. There used to be
> a limitation in lustre where the OST couldn't be bigger than 2TB when
> having 32bit clients. Is this still true?  The documentation says the
> current limit is 8TB without specifying anything about 32bit clients.

This limitation was in older 32-bit kernels on the server.  The kernel
has been fixed to allow up to 16TB DEVICES on 32-bit kernels, though
Lustre currently only supports up to 8TB ldiskfs filesystems on the
OSTs (regargless of 32- or 64-bit kernels).

Testing and fixing is currently underway to allow up to 16TB ldiskfs
filesystems, likely finishing in the next month or two.

Eventually (once the upstream ext4 and e2fsprogs code is fixed) to support
even larger ldiskfs filesystems.  That will likely not be until 2.6.26
kernels or later.

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