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Date: Thu, 12 May 2005 12:55:52 -0700
From: Steve Kargl <sgk@troutmask.apl.washington.edu>
To: Michael Hopkins <michael.hopkins@hopkins-research.com>
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cc: "freebsd-amd64@freebsd.org" <freebsd-amd64@freebsd.org>
Subject: Re: Actual benefits of amd64 over i386
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On Thu, May 12, 2005 at 08:43:46PM +0100, Michael Hopkins wrote:

> I have been suffering quite a bit of frustration recently with many ports
> that I need being 'i386 only' and no straightforward fixes.  Maybe amd64
> could be described as 'tier 1.5'  ;o)

Look in the port's Makefile for the i386 only flag.  Remove it
and trying building on amd64.  Many ports run fine, but the
porter either does not have access to amd64 or the port simply
has not been tested on amd64.

> Can I ask for honest opinions here on what speed (or other?) benefits I
> should get by running amd64 over i386?  I will never be using more than
> about 1 G of memory on this particular machine so memory limit is not an
> issue.  Maybe I should just rebuild the machine as i386?

amd64 should have more registers available for scheduling.

>  C/C++ maths code (which must run as fast as possible).

"C/C++ math code" and "run as fast as possible" are mutually
exclusive. :-)

-- 
Steve