From owner-freebsd-sparc Wed Jan 26 0:19:22 2000 Delivered-To: freebsd-sparc@freebsd.org Received: from feral.com (feral.com [192.67.166.1]) by hub.freebsd.org (Postfix) with ESMTP id 7A65715154 for ; Wed, 26 Jan 2000 00:19:19 -0800 (PST) (envelope-from mjacob@feral.com) Received: from beppo.feral.com (beppo [192.67.166.79]) by feral.com (8.9.3/8.9.3) with ESMTP id AAA31611; Wed, 26 Jan 2000 00:19:18 -0800 Date: Wed, 26 Jan 2000 00:19:15 -0800 (PST) From: Matthew Jacob Reply-To: mjacob@feral.com To: Lyndon Griffin Cc: freebsd-sparc@FreeBSD.ORG Subject: Re: SS 470 info In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-sparc@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org The SparcServer 600 is sun4m- Sparc Reference MMU- like the Motorola 68851 MMU- a root pointer and multilevel page tables in real memory. On Wed, 26 Jan 2000, Lyndon Griffin wrote: > How does the 470 compare to the 600, in this respect? > > <:) Lyndon Griffin > http://www.bsd4us.org > > On Tue, 25 Jan 2000, Matthew Jacob wrote: > > > > > Not significantly different- just more- it's a 3rd level MMU extension to the > > 2 level sun4c/sun4/sun3 stuff. On the older machines it was a resource > > limitation of pte's mapped by PMEG (page map entry group). The sunray MMU > > added SMEG (system map entry group) to map groups of PMEGs. > > > > If you mean "Is it different from other sparcs", i.e., sun4m/sun4u, yes- > > sun4m/sun4u both have real memory page tables. The older sun machines were > > more like the VAX- restricted amounts of SRAM to provide a multilevel TLB. > > For the time an excellent but cheap design. With respect to flexibility, gawd > > awful. > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-sparc" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-sparc" in the body of the message