From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: util-linux-owner@vger.kernel.org Received: from mail-pd0-f169.google.com ([209.85.192.169]:61717 "EHLO mail-pd0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752884AbaJ1DZV (ORCPT ); Mon, 27 Oct 2014 23:25:21 -0400 Received: by mail-pd0-f169.google.com with SMTP id y10so2571248pdj.28 for ; Mon, 27 Oct 2014 20:25:21 -0700 (PDT) Received: from [192.168.1.2] ([59.89.143.167]) by mx.google.com with ESMTPSA id pl3sm186287pbb.50.2014.10.27.20.25.18 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 27 Oct 2014 20:25:20 -0700 (PDT) Message-ID: <544F0C88.1080807@gmail.com> Date: Tue, 28 Oct 2014 08:54:56 +0530 From: dE MIME-Version: 1.0 To: util-linux@vger.kernel.org Subject: Re: fdisk and 2048 sectors obsession. References: <544E923E.6050406@gmail.com> <544E97ED.7040406@earthlink.net> In-Reply-To: <544E97ED.7040406@earthlink.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: util-linux-owner@vger.kernel.org List-ID: On 10/28/14 00:37, Felix Miata wrote: > dE composed on 2014-10-28 00:13 (UTC+0530): > >> I was learning about GPT when I noticed this behavior of fdisk which I >> never though about before. >> Regardless of the partition table, fdisk always starts the first >> partition at 2048. In reality, the maximum size required by the gap >> between MBR and the 1st partition is a single sector, which's used by >> GRUB 1.5. GPT doesn't need this space at all. >> Then extended partitions too have a gap of 2048 sectors. >> Why this behavior? > http://www.seagate.com/tech-insights/advanced-format-4k-sector-hard-drives-master-ti/ > may provide some insight WRT performance issues ensuing from other start > sector selections. But that works even with multiples of 8. So we can start from sector 8 in MBR and 40 in GPT. Also I'm pretty sure fdisk uses 2048 even with -b 4096, but unfortunately I get -- *** Error in `fdisk': malloc(): memory corruption: 0x0000000002507330 *** with that switch.