Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 21 Feb 2002 08:21:00 +0100
From:      =?ISO-8859-1?B?U/hyZW4gTmVpZ2FhcmQ=?= <neigaard@e-box.dk>
To:        Erik Trulsson <ertr1013@student.uu.se>
Cc:        Alex <akruijff@dds.nl>, Alex <FreeBSD@cybertron.tmfweb.nl>, questions@freebsd.org
Subject:   Re[2]: OT: Re: Max RAM supported by Hardware
Message-ID:  <193651536.20020221082100@e-box.dk>
In-Reply-To: <20020220220028.GA21515@student.uu.se>
References:  <1556477954.20020220210026@e-box.dk> <14217053982.20020220215646@cybertron.tmfweb.nl> <15518324328.20020220221756@cybertron.tmfweb.nl> <20020220220028.GA21515@student.uu.se>

next in thread | previous in thread | raw e-mail | index | archive | help
Wednesday, February 20, 2002, 11:00:28 PM, Erik wrote:

ET> On Wed, Feb 20, 2002 at 10:17:56PM +0100, Alex wrote:
ET> Sorry, but you just don't seem to understand how things work.
ET> With a 32-bit address space the maximum amount of memory that can be
ET> addressed is 2^32 = 4Gigabytes. This is also the max that FreeBSD
ET> supports on i386.

Great - So I did understand it right then :)


ET> There should be no need to recompile anything.
ET> (Although there has been some reports of problems with >2G but I think
ET> that has been fixed now.)

That sounds super, I love FreeBSD, it's so much easier than any other
OS I have tried :)


ET> Modern x86 CPUs (Pentium Pro and later) can address up to 2^36 (=64G)
ET> bytes of memory.  To use the extra memory requires you to play some
ET> tricks with the MMU (Memory Management Unit) to map the memory into the
ET> 4G address space. Even then you cannot really have a single process use
ET> more than 4G.  This capability is currently not supported by FreeBSD
ET> and to support it would require some fairly serious rewriting of parts
ET> of the kernel.

Ok

ET> On Alpha the max that is supported is 2G. I am not sure why that
ET> limitation exists but it does.

Strange - It should be able to support much much more. I guess FreeBSD
is mostly for i386, right? Not much being done for other platforms?

--
Med venlig hilsen/Best regards,
 Søren Neigaard mailto:neigaard@e-box.dk


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?193651536.20020221082100>