From owner-freebsd-questions@FreeBSD.ORG Mon Mar 12 18:48:59 2007 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id A5F2716A408 for ; Mon, 12 Mar 2007 18:48:59 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from mail-out3.apple.com (mail-out3.apple.com [17.254.13.22]) by mx1.freebsd.org (Postfix) with ESMTP id 8BE2A13C4C1 for ; Mon, 12 Mar 2007 18:48:59 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from relay5.apple.com (a17-128-113-35.apple.com [17.128.113.35]) by mail-out3.apple.com (8.13.8/8.13.8) with ESMTP id l2CImxmK000229; Mon, 12 Mar 2007 11:48:59 -0700 (PDT) Received: from relay5.apple.com (unknown [127.0.0.1]) by relay5.apple.com (Symantec Mail Security) with ESMTP id 50C0629C004; Mon, 12 Mar 2007 11:48:59 -0700 (PDT) X-AuditID: 11807123-9d11bbb000004462-3d-45f5a09bc224 Received: from [17.214.13.96] (cswiger1.apple.com [17.214.13.96]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by relay5.apple.com (Apple SCV relay) with ESMTP id 3BEEC30400B; Mon, 12 Mar 2007 11:48:59 -0700 (PDT) In-Reply-To: References: <6.0.0.22.2.20070309094909.024c9dd0@mail.computinginnovations.com> <6.0.0.22.2.20070309133935.024b8fd0@mail.computinginnovations.com> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: Content-Transfer-Encoding: 7bit From: Chuck Swiger Date: Mon, 12 Mar 2007 11:48:58 -0700 To: Dima Sorkin X-Mailer: Apple Mail (2.752.2) X-Brightmail-Tracker: AAAAAA== Cc: freebsd-questions@freebsd.org Subject: Re: limitiation on memory allocation X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Mar 2007 18:48:59 -0000 On Mar 12, 2007, at 11:20 AM, Dima Sorkin wrote: > 2) 'maxdsiz' - Yes, as long as I keep 'maxdsiz + maxssiz' below > physical > memory size - everything is fine. Single process allocates > successfully > up to 'maxdsiz'. > When tried to put 'maxdsiz' > phys mem size, > indeed the system failed to boot, in all modes: > multiuser, singleuser, safe. > > So I derive from here that there is no way to cause a _single process_ > on FreeBSD to allocate more than physical memory size (?) It is certainly possible to configure FreeBSD to allow a single process to access more memory than is phyiscally installed. For example, I have a machine with 512MB of RAM, and set: kern.dfldsiz="1G" ...in /boot/loader.conf, and this works just fine. Admittedly, when a process does exceed 512MB in dsize, the system starts swapping quite a bit, but that's how virtual memory works. However, you cannot set maxdsiz greater than 4GB [1] if you are running a 32-bit version of FreeBSD. Enabling PAE will let the kernel access more than 4GB of physical RAM, but nothing is going to let a 32-bit system give more than 4 GB [1] to a single process...if you want to do that, then you'll need to switch to running a 64-bit version of FreeBSD. -- -Chuck [1]: Well, 3.5GB or 3GB, actually...due to the top portion of address space being occupied by PCI device space and the kernel.