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Date: 10 Apr 2015 17:12:40 -0000
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From: "John Levine" <johnl@iecc.com>
To: freebsd-questions@freebsd.org
Subject: Re: How FreeBSD manage more than 4GB on 32 bits architecture
In-Reply-To: <552794F7.60306@asim.lip6.fr>
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Cc: Pierre-Yves.Peneau@lip6.fr
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>> If you need more than that, you use a 64 bit architecture.
>
>But it exists :-)  We have a simulate environment, and a real
>prototype which have 24 clusters (i.e. 96 CPUs) and 96GB of physical
>memory. All of this with 32 RISC processors.

I believe they can build it.  But I think you will find it very
difficult to program.  Every system that requires programs to be
decomposed into cooperating loosely coupled parts to get full
performance has hit this wall.

>Thank you for your advices. I agree with you, but it's an internship,
>I can't say "Please, would you like to change all your CPUs for me ?"
>:-)   Moreover, the main challenge is to deal with huge memory with 32
>bits processors (only RISC), I think it's really interesting.

It'll certainly be a learning experience, even if what you learn is
"don't do that again."  Good luck.

R's,
John