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From: Jon Dama <jd@ugcs.caltech.edu>
To: Ivan Voras <ivoras@fer.hr>
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Cc: freebsd-current@freebsd.org, Giorgos Keramidas <keramida@freebsd.org>
Subject: Re: Errno man page
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> becoming as common as 32bit, maybe a note should be added about the
> differences (also AFAIK: there's no point in having RAM+swap > 4GB on
> 32bit machines?)

This is patently untrue.  In theory the maximum swap you can configure
(and use) on i386 is 2TB * 4 swap devices... however, certain limits (see
1) make this ~32GB per swap device * 4 swap devices.  And in practice this
number is further limited by the size of kva (see, Matt Dillon's comment
in note 2).  He estimates 16GB out of the box and 60GB with KVA tuning as
the limit of swap on i386.

swap space != address space.

note 1: http://lists.freebsd.org/pipermail/freebsd-amd64/2005-May/004700.html
        * though this explicitly refers to amd64, the comment applies
          equally to i386

note 2: http://kerneltrap.org/node/323

If anything, there should be notation reminding people that RAM + SWAP is
not constrained by 4GBs on i386.

-Jon