From owner-freebsd-hackers Sun Dec 9 0:21:41 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from apollo.backplane.com (apollo.backplane.com [216.240.41.2]) by hub.freebsd.org (Postfix) with ESMTP id AB48837B416 for ; Sun, 9 Dec 2001 00:21:39 -0800 (PST) Received: (from dillon@localhost) by apollo.backplane.com (8.11.6/8.9.1) id fB98LbQ36051; Sun, 9 Dec 2001 00:21:37 -0800 (PST) (envelope-from dillon) Date: Sun, 9 Dec 2001 00:21:37 -0800 (PST) From: Matthew Dillon Message-Id: <200112090821.fB98LbQ36051@apollo.backplane.com> To: Terry Lambert Cc: Varshavchick Alexander , freebsd-hackers@FreeBSD.ORG Subject: Re: 4G phisical memory kernel trap References: <3C0F2E1B.7F933520@mindspring.com> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG :Varshavchick Alexander wrote: :> > For this to work, you really MUST address the machdep.c problems. :> :> So how can it be done, are there any patches for machdep.c, or is it :> solved in 4.4-stable kernel? : :Matt Dillon took a sideways stab at addressing a bit of these :issues. They didn't do everything that I thought was needed, :but he posted the diffs to the -current list, and may have :committed them to -current (look for them there). It's fixed in -stable and -current. Basically I comitted code that puts a cap on the size of certain KVM blocks that were previously scaled according to the amount of physical memory. Since KVM is limited to the upper quarter of VM (1G) by default, the scaling of these structures blew out our KVM space and paniced machines with large amounts of memory. I also cut the size of the swap map reservation in half. It isn't perfect, but I've tested it on 4G machines and it does work. What we really need to do is rearrange the kernel such that we can calculate all the KVM requirements and scale them properly before actually trying to allocate any of them. :sometimes useful). I will cover where and how to do this for :non-4M pages, in my article. Go for it! I look forward to reading your article Terry! :-- Terry -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message