From owner-freebsd-hackers Fri Oct 29 3:14:25 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from wombat.is.fh-hamburg.de (wombat.is.fh-hamburg.de [141.22.192.33]) by hub.freebsd.org (Postfix) with ESMTP id C2F5714CF7 for ; Fri, 29 Oct 1999 03:14:18 -0700 (PDT) (envelope-from kuehl@lgk.de) Received: from issus.susan.fh-hamburg.de (issus.susan.fh-hamburg.de [141.22.100.39]) by wombat.is.fh-hamburg.de (8.9.3/8.9.3) with SMTP id MAA20649; Fri, 29 Oct 1999 12:13:59 +0200 (MET DST) Received: from pisces.susan.fh-hamburg.de by issus.susan.fh-hamburg.de (5.65v4.0/1.1.10.5/19Aug97-1156AM) id AA25481; Fri, 29 Oct 1999 12:10:40 +0200 Message-Id: X-Mailer: XFMail 1.3 [p0] on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit Mime-Version: 1.0 In-Reply-To: <199910290502.WAA03970@dingo.cdrom.com> Date: Fri, 29 Oct 1999 12:05:55 +0200 (CEST) Reply-To: kuehl@lgk.de From: Lars Gerhard Kuehl To: Mike Smith Subject: Re: Limitations in FreeBSD Cc: hackers@FreeBSD.ORG, Chuck Youse Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On 29-Oct-99 Mike Smith wrote: >> > That's correct; it's why the ia32 architecture has a '32' in its name. >> >> I don't believe that's true. I don't have any hard evidence within easy >> reach, but with the introduction of the Pentium, the address space was >> increased. A user process, of course, can only have 4G of addressible >> space (32-bit addresses) but the OS can map pages of the 4G space into a >> larger area. The Pentium and successors can address more than 4G _physical_ memory, 32 or 64GB, I need to look into the manual. But that feature needs to be explicitely enabled. >> >> Something to do with 4MB pages instead of 4K pages. >> >> Again, I could be wrong on this one. With extended physical addressing enabled the bigger page size is 2MB instead of 4 MB. > Think about it for a second. How big is a pointer? The Intel architecture still supports segmented memory, so the effective maximum pointer size is 48 bit. Lars To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message