Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751425AbXAVGpa (ORCPT ); Mon, 22 Jan 2007 01:45:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751453AbXAVGpa (ORCPT ); Mon, 22 Jan 2007 01:45:30 -0500 Received: from scrye.com ([216.17.180.1]:48016 "EHLO mail.scrye.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751425AbXAVGp3 (ORCPT ); Mon, 22 Jan 2007 01:45:29 -0500 Subject: Re: PROBLEM: KB->KiB, MB -> MiB, ... (IEC 60027-2) From: Tony Foiani Reply-To: Tony Foiani X-Attribution: Tkil CC: jengelh@linux01.gwdg.de (Jan Engelhardt), David Schwartz , Leon Woestenberg , linux-kernel@vger.kernel.org References: Date: Sun, 21 Jan 2007 23:45:28 -0700 In-Reply-To: (Jan Engelhardt's message of "Sun, 21 Jan 2007 22:12:55 +0100 (MET)") Message-ID: User-Agent: Gnus/5.1007 (Gnus v5.10.7) XEmacs/21.5-b27 (linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1699 Lines: 41 >>>>> "Tony" == Tony Foiani writes: Tony> How fast is your Ethernet port? 100Mbps or 95.37Mbps? >>>>> "Jan" == Jan Engelhardt writes: Jan> Same lie like with harddrives. It's around 80, not 100. But it Jan> depends on how you look at it. 80 for Layer3, possibly a little Jan> more for Layer2/1. No, it's not the same lie. The physical media -- as presented to the next higher layer -- really has 100Mbps capability. Likewise, the "physical media" of a hard drive (as seen outside the controller on the disk) really is 500GB/465GiB (or whatever). [1] The overhead caused by Ethernet frames (level 2) and then IP packets (level 3) and then TCP or UDP (level 4) are more closely related to the losses you get on filesystem overhead (superblock, inodes, directories) and "slack" in block-allocated systems (having to round sizes up to the next 512 or whatever). [2] The problem is that a drive labelled "500GB" on its packaging is displayed as "465GB" on the computer. The fix is to have the computer display either "500GB" or "465GiB". t. [1] SFAIK, what's really on hard drive platters anymore is something much closer to "symbols", not just 1s and 0s. In the same way that "baud" is "symbols per second", the actual thingies on the platters are symbols, and it's up to the drive electronics to make sense of them. [2] Level numbers from: http://en.wikipedia.org/wiki/TCP/IP_model - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/