From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <3e1162e60711160643h329d4d7fh60bb21de30aae89b@mail.gmail.com>
Date: Fri, 16 Nov 2007 06:43:27 -0800
From: "David Leimbach" <leimy2k@gmail.com>
To: "Fans of the OS Plan 9 from Bell Labs" <9fans@cse.psu.edu>
Subject: Re: [9fans] Current status of amd64 port?
In-Reply-To: <8438B414-BE32-4A89-886B-23547C5B6D7F@utopian.net>
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On Nov 15, 2007 4:11 PM, Joshua Wood <josh@utopian.net> wrote:
> > 64 bits is neither here nor there in a vaccuum.  you want 64 bits if
> > a) you need more than 4GB of memory, or
> > a) those extra registers and direct vlong really matter for
> > performance.
> > otherwise it's just a lot of extra zeros.
> > it's kind of silly to run 64-bit linux on a machine with <= 4GB of
> > memory.
> >
>
> Some testing we did about a year ago showed that (for us) even the
> extra registers -- I always thought the sweetest-sounding part of the
> deal -- help sometimes, but not always. I ended up thinking it was
> because caches hadn't necessarily grown apace with address space. The
> distance between cpu and main memory seemed to have expanded again...
>

Intel or AMD?  I've found AMDs memory architecture for 64bit stuff to
pretty much stomp Intel nearly every time.