Date: Sat, 13 Jul 2002 19:27:59 -0700
From: Marc MERLIN
To: Brian Chrisman
Cc: [a list]
Subject: Re: block device size limits under linux
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On Sat, Jul 13, 2002 at 06:55:19PM -0700, Brian Chrisman wrote:
> > Anyone know what the block device size limits are under linux? One of
> > my customer is claiming it's 1 Tb, but I'm fairly certain it's 2 Tb. I
> > know I've used 1.1 Tb 3ware arrays.
> I had the impression it was *really* large... of course, just having a
> large block device doesn't mean there's a filesystem/tools which will
> read it...

Yep, but:

Although many of the filesystems in common use can cope with large files and
large disc volumes, the Linux kernel limits the size of a filesystem, and
the maximum size of a file, in various places. In effect under current
(2.5.15) linux, the maximum file system size is about 1TB, and the maximum
file size is just under 2TB (actually, 0x1fffffff000 bytes) on a 32-bit
machine with 4k pages. It turns out that this limitation is extended (by use
of ints where there should be longs) to 64-bit platforms as well.

So I was confused, the 2TB limit is for a file. Apparently a device is
indeed limited to 1TB.

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