From owner-freebsd-stable@FreeBSD.ORG Sun Nov 4 21:11:26 2007 Return-Path: Delivered-To: freebsd-stable@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C632616A419 for ; Sun, 4 Nov 2007 21:11:26 +0000 (UTC) (envelope-from petefrench@ticketswitch.com) Received: from angel.ticketswitch.com (angel.ticketswitch.com [IPv6:2002:57e0:1d4e::1]) by mx1.freebsd.org (Postfix) with ESMTP id 897AE13C4B2 for ; Sun, 4 Nov 2007 21:11:26 +0000 (UTC) (envelope-from petefrench@ticketswitch.com) Received: from smaug.rattatosk ([10.50.50.2]) by angel.ticketswitch.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.67 (FreeBSD)) (envelope-from ) id 1Iomkf-000EnK-Lm for freebsd-stable@FreeBSD.ORG; Sun, 04 Nov 2007 21:11:25 +0000 Received: from dilbert.rattatosk ([10.50.50.6] helo=dilbert.ticketswitch.com) by smaug.rattatosk with esmtp (Exim 4.67 (FreeBSD)) (envelope-from ) id 1Iomkf-000PdH-K1 for freebsd-stable@FreeBSD.ORG; Sun, 04 Nov 2007 21:11:25 +0000 Received: from petefrench by dilbert.ticketswitch.com with local (Exim 4.68 (FreeBSD)) (envelope-from ) id 1Iomkf-0007HH-JC for freebsd-stable@FreeBSD.ORG; Sun, 04 Nov 2007 21:11:25 +0000 To: freebsd-stable@FreeBSD.ORG Message-Id: From: Pete French Date: Sun, 04 Nov 2007 21:11:25 +0000 Cc: Subject: Best way to use more that 4 gigs of memory ? X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 04 Nov 2007 21:11:26 -0000 I have been doing some experiments with runnign 32 bit processed on and amd64 kernel over the last couple of days and am wondering what the general feel is for the best way to use over 4 gigs of memory. As far as I can see I have 3 options: 1) amd64 kernel + 64 bit processes 2) amd64 kernel + 32 bit processes 3) i386 kernel with PAE and 32 bit processes I was initially thinking that option 1 was the best, but benchmarking it the programs take 3 times longer to run that option 2! This astounds me and I intend to investigate why, but given it is rue then that rules it out as a viable solution for deploying stuff. Which leaves either 32 bit processes on a 64 bit kernel or alternatively running under PAE on a 32 bit kerenel. I don't know a lot about PAE and was wondering if anyone had any advice either way as to which wouldbe the most stable and/or best performing. cheers, -pcf.