RE: 2.5.28 and partitions

From: Alexander Viro (viro@math.psu.edu)
Date: Thu Jul 25 2002 - 06:44:40 EST


On Wed, 24 Jul 2002, Linus Torvalds wrote:

> Note that there is one place where 64 bits is simply _too_ expensive, and
> that's the page cache. In particular, the "index" in "struct page". We
> want to make "struct page" _smaller_, not larger.
>
> Right now that means that 16TB really is a hard limit for at least some
> device access on a 32-bit machine with a 4kB page-size (yes, you could
> make a filesystem that is bigger, but you very fundamentally cannot make
> individual files larger than 16TB).

ITYM "8Tb" - indices are signed, IIRC. OTOH, it's not 2^31 * PAGE_SIZE -
it's 2^31 * PAGE_CACHE_SIZE, which can be bigger.

Al, still thinking that anybody who does mkfs.<whatever> on a multi-Tb
device should seek professional help of the kind they don't give on l-k...

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