From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from slmp-550-94.slc.westdc.net ([50.115.112.57]:45349 "EHLO slmp-550-94.slc.westdc.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751358AbaFVBel convert rfc822-to-8bit (ORCPT ); Sat, 21 Jun 2014 21:34:41 -0400 Received: from c-75-70-18-61.hsd1.co.comcast.net ([75.70.18.61]:59481 helo=[192.168.1.145]) by slmp-550-94.slc.westdc.net with esmtpsa (TLSv1:AES128-SHA:128) (Exim 4.82) (envelope-from ) id 1WyWfw-00303p-FK for linux-btrfs@vger.kernel.org; Sat, 21 Jun 2014 19:34:32 -0600 Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 6.6 \(1510\)) Subject: Re: btrfs on whole disk (no partitions) From: Chris Murphy In-Reply-To: Date: Sat, 21 Jun 2014 19:34:30 -0600 Message-Id: <6CA8020B-EB92-4A44-8AA5-3F69709F81F2@colorremedies.com> References: <2316027.LZEnVG8laK@xev> To: Btrfs BTRFS Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Jun 21, 2014, at 1:12 PM, Daniel Cegiełka wrote: > 2014-06-19 2:07 GMT+02:00 Russell Coker : > >> For boot disks I use the traditional partitioning system. So far I don't run >> any systems that have a boot disk larger than 2TB so I haven't needed to use >> GPT. >> >> I have a BTRFS RAID-1 on 2*3TB disks which have no partition tables, when the >> filesystem is going to use the entire device and there's no boot loader there >> is no reason to have a partition table. > > ok, but what about alignment? This can have a significant impact on performance. 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. Chris Murphy