From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 9 Jan 2001 09:07:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 9 Jan 2001 09:07:34 -0500 Received: from zeus.kernel.org ([209.10.41.242]:24781 "EHLO zeus.kernel.org") by vger.kernel.org with ESMTP id ; Tue, 9 Jan 2001 09:07:11 -0500 Date: Tue, 9 Jan 2001 14:05:04 +0000 From: "Stephen C. Tweedie" To: Venkatesh Ramamurthy Cc: "'Pavel Machek'" , adefacc@tin.it, linux-kernel@vger.kernel.org, Stephen Tweedie Subject: Re: Confirmation request about new 2.4.x. kernel limits Message-ID: <20010109140504.D4284@redhat.com> In-Reply-To: <1355693A51C0D211B55A00105ACCFE64E95137@ATL_MS1> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <1355693A51C0D211B55A00105ACCFE64E95137@ATL_MS1>; from Venkateshr@ami.com on Mon, Jan 08, 2001 at 11:11:05PM -0500 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Mon, Jan 08, 2001 at 11:11:05PM -0500, Venkatesh Ramamurthy wrote: > > > Max. RAM size: 64 GB (any slowness > accessing RAM over 4 GB > * with 32 bit machines ?) > Imore than 4GB in RAM is bounce buffered, so there is performance > penalty as the data have to be copied into the 4GB RAM area Any memory over 1GB is bounce-buffered, but we don't use that memory for anything other than process data pages or file cache, so only swapping and disk IO to regular files gets the extra copy. In particular, things like network buffers are still all kept in the low 1GB so never need to be buffered. --Stephen - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/