From owner-freebsd-questions Thu Mar 14 8:45: 8 2002 Delivered-To: freebsd-questions@freebsd.org Received: from web.cs.ndsu.nodak.edu (web.cs.ndsu.NoDak.edu [134.129.125.7]) by hub.freebsd.org (Postfix) with ESMTP id 8E22637B420 for ; Thu, 14 Mar 2002 08:44:55 -0800 (PST) Received: (from tinguely@localhost) by web.cs.ndsu.nodak.edu (8.11.4/8.11.4) id g2EGisl21602; Thu, 14 Mar 2002 10:44:54 -0600 (CST) (envelope-from tinguely) Date: Thu, 14 Mar 2002 10:44:54 -0600 (CST) From: mark tinguely Message-Id: <200203141644.g2EGisl21602@web.cs.ndsu.nodak.edu> To: freebsd-questions@FreeBSD.ORG, wam@HiWAAY.net Subject: Re: Maximizing user-process address space under 4.4 In-Reply-To: <3C900211.EA1EEF62@HiWAAY.net> Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG > I recently installed FreeBSD 4.4 (Wind river, not a copy) on my 933 > MHz Intel box. I want to use the machine to do finite element analysis & > want to be able to address as much of the 4 GB 32 bit address space as > possible to run big jobs (I was stuck at 2 GB w/ Linux, that's why > FreeBSD). I have talked w/ some people who gave me some suggestions, but > most were for 4.5, not 4.4. I can use 2 GB now, but whenever I recompile > the kernel w/ larger MAXDSIZ parameter (larger than 2 GB), the compile & > install go OK, but the kernel won't boot. Someone said something about > trying to cut down on a parameter called KVA_PAGES, but that's 4.5, not > 4.4. What is the equivalent parameters(s) under 4.4 ? Thanks in advance > for your time. The kernel won't boot because you ran out of Kernel Virtual Memory because of the high number of disk buffer buffers (which are automatically calculated to be a percentage of your physical memory). To fix this problem, either upgrade to FreeBSD 4.5/stable or The *increase* the kernel virtual address space (which will also decrease your user virtual address, which is what you do *not* want to do). The handbook and an -hackers mail from Terry Lambert (Dec 6, 2001 "Re: 4G phisical memory kernel trap") explains how to increase the kernel virtual memory. If you want to look in -hackers mailing list for articles by Matt Dillon in the Aug 19, 2001 time frame there is an explaination of the problem and some patches that scale back the number of disk buffers when the machine has lots of physical memory. BUT I would highly recommend FreeBSD 4.5/stable over a single patch. --mark tinguely. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message