From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from atl4mhob14.myregisteredsite.com ([209.17.115.52]:41038 "EHLO atl4mhob14.myregisteredsite.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751378AbaFVOp5 (ORCPT ); Sun, 22 Jun 2014 10:45:57 -0400 Received: from mailpod1.hostingplatform.com (atl4obmail02pod1.mgt.hosting.qts.netsol.com [10.30.71.114]) by atl4mhob14.myregisteredsite.com (8.14.4/8.14.4) with ESMTP id s5MEjt43019085 for ; Sun, 22 Jun 2014 10:45:55 -0400 Message-ID: <53A6EC60.3030606@chinilu.com> Date: Sun, 22 Jun 2014 07:46:56 -0700 From: George Mitchell Reply-To: george@chinilu.com MIME-Version: 1.0 To: Roman Mamedov CC: linux-btrfs@vger.kernel.org Subject: Re: btrfs on whole disk (no partitions) References: <2316027.LZEnVG8laK@xev> <6CA8020B-EB92-4A44-8AA5-3F69709F81F2@colorremedies.com> <53A6DDAD.8070804@chinilu.com> <20140622201140.08e74b7e@natsu> In-Reply-To: <20140622201140.08e74b7e@natsu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 06/22/2014 07:11 AM, Roman Mamedov wrote: > On Sun, 22 Jun 2014 06:44:13 -0700 > George Mitchell wrote: > >> On 06/22/2014 12:49 AM, Imran Geriskovan wrote: >>>> The 64KB Btrfs bootloader pad is 8 sector aligned, so for 512e AF disks >>>> there's no problem formatting the whole drive. The alignment problem >>>> actually happens when partitioning it, using old partition tools that don't >>>> align on 8 sector boundaries. There are some such tools still floating >>>> around. >>> A 'somewhat' related question: >>> >>> So called Advanced Format drives has 4K physical sector size, >>> however they report 512B logical sector size. >>> >>> How does linux kernel access those drives? >>> 512B or 4K at a time? >> This is a problem related to Western Digital drives. They lie in order >> to be compatible with older versions of Windows. > Wake up and smell the coffee. > > Device Model: HGST HTE725050A7E630 > Sector Sizes: 512 bytes logical, 4096 bytes physical > > > Device Model: TOSHIBA DT01ACA050 > Sector Sizes: 512 bytes logical, 4096 bytes physical > > > The "AF" standard as accepted by the industry does include this "lying", and > it's not just WD doing this by any stretch of the imagination. Aside from > USB-only drives (which lack the ability to be plugged into SATA), no one can > afford to produce and a drive incompatible with Windows these days. In fact > I'd be glad if you could support your Seagate 4K claim by any model names and > their smartctl output. > Here is the story: http://johannes-bauer.com/linux/wdc/?menuid=3