Subject: Re: Huge (> 1TB) disk
To: Perry E. Metzger <>
From: Thor Lancelot Simon <>
List: tech-kern
Date: 05/13/2002 22:59:07
On Mon, May 13, 2002 at 08:39:45PM -0400, Perry E. Metzger wrote:
> Luke Mewburn <> writes:
> > Actually, I don't think that this will help, at least for ffs file systems. 
> > You need to crank the sector size to 1024 bytes from 512 bytes to have an
> > ffs file system larger than 1 TB (1024 GB), because ffs has a signed 32 bit
> > quantity for disk block addresses, and 2^(31+9) == 1 TB.
> We really should fix this. The limitations in FFS are largely
> artificial -- an ffs2 that did 64 bit quantities for all these things
> would be very straightforward to produce.

If we were going to do *that*, it would make sense to rip out all the
rotational placement and other obsolete complexity at the same time.  But
once you start to go there, it starts to look an *awful* lot like it might
just make sense to build a simple filesystem that mostly trusts the disk to
place blocks.