From owner-freebsd-questions Mon Jul 10 18:51:56 1995 Return-Path: questions-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id SAA29744 for questions-outgoing; Mon, 10 Jul 1995 18:51:56 -0700 Received: from Root.COM (implode.Root.COM [198.145.90.1]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id SAA29737 for ; Mon, 10 Jul 1995 18:51:54 -0700 Received: from corbin.Root.COM (corbin [198.145.90.18]) by Root.COM (8.6.11/8.6.5) with ESMTP id SAA10011; Mon, 10 Jul 1995 18:51:32 -0700 Received: from localhost (localhost [127.0.0.1]) by corbin.Root.COM (8.6.11/8.6.5) with SMTP id SAA02421; Mon, 10 Jul 1995 18:52:25 -0700 Message-Id: <199507110152.SAA02421@corbin.Root.COM> To: a00776@giant.mindlink.net (Toomas Losin) cc: freebsd-questions@freebsd.org Subject: Re: 2.0.5 64 meg RAM limit? In-reply-to: Your message of "Mon, 10 Jul 95 12:57:35 PDT." From: David Greenman Reply-To: davidg@Root.COM Date: Mon, 10 Jul 1995 18:52:24 -0700 Sender: questions-owner@freebsd.org Precedence: bulk >I've got an interesting situation with our news server, running 2.0.5R. It's >just been expanded from 64 megs to 128 but the OS doesn't recognize the upper >64. To the best of my knowledge the BIOS is setup correctly. > >Is there a default 64 meg limit? Can I specify an option to tell the kernel >how much memory there is? I've been digging through the source but nothing >obvious jumps out at me (other than hard coding the amount - something I don't >really want to do). FreeBSD gets the memory size from the 16bit K-bytes field in the BIOS RTC memory. Since this is 16bits large, the maximum that it can represent is 65535K bytes (64MB). The only way to get FreeBSD to see more memory at the moment is to add: options "MAXMEM=131072" (or whatever K-bytes you have) ...to your kernel config file. In the future FreeBSD will get the information in a different way (using special BIOS calls at boot time), but there isn't sufficient space in the boot blocks to do this and thus it first requires a 3 stage boot. -DG