Subject: Re: NetBSD, apple fibre-channel card & 2.8TB Xserve-RAID
To: <>
From: David Laight <>
List: tech-kern
Date: 12/03/2004 20:39:57
On Fri, Dec 03, 2004 at 12:11:42PM -0800, Jason Thorpe wrote:
> On Dec 3, 2004, at 12:03 PM, Greg A. Woods wrote:
> >Of course since the real limit in disklabels and FFS is 2^32 sectors 
> >per partition and per filesystem the array has to be re-configured to
> >present separate LUNs of no more than one terabyte each.
> FFSv2 in 2.0/-current should allow you to use up to 2TB.
> Yes, disklabels are a problem...

The limit for FFSv1 is 2^31 fragments, with large fragments you could
have > 2^32 sectors.

However both FFSv1 and FFSv2 are limited by the label - Current might
have enough patches to support 2^32-1 sectors.

Note that FFSv2 wil only support 2^31 inodes per filesystem, and that the
large number of cylinder groups probably does little to improve performance.

Interestingly the kernel has support to 64bit disk sector numbers :-)


David Laight: