Re: [00/17] Large Blocksize Support V3

Theodore Tso
2007-04-27T16:55:40Z

On Thu, Apr 26, 2007 at 10:15:28PM -0700, Andrew Morton wrote:
> And hardware gets better. If Intel & AMD come out with a 16k pagesize
> option in a couple of years we'll look pretty dumb. If the problems which
> you're presently having with that controller get sorted out in the next
> generation of the hardware, we'll also look pretty dumb.

Unfortunately, this isn't a problem with hardware getting better, but
a willingness to break backwards compatibility.

x86_64 uses a 4k page size to avoid breaking 32-bit applications. And
unfortunately, iirc, even 64-bit applications are continuing to depend
on 4k page alignments for things like the text and bss segments. If
the userspace ELF and other compiler/linker specifications were
appropriate written so they could handle 16k pagesizes, maybe 5 years
from now we could move to a 16k pagesize. But this is going to
require some coordination between the userspace binutils folks and
AMD/Intel in order to plan such a migration.

- Ted