From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:51784 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752650AbaLSWGR (ORCPT ); Fri, 19 Dec 2014 17:06:17 -0500 Message-ID: <5494A152.7030203@fb.com> Date: Fri, 19 Dec 2014 17:06:10 -0500 From: Josef Bacik MIME-Version: 1.0 To: Phillip Susi , Daniele Testa CC: Subject: Re: btrfs is using 25% more disk than it should References: <54947432.5010107@ubuntu.com> <5494955C.3020603@fb.com> <54949E60.7010201@ubuntu.com> In-Reply-To: <54949E60.7010201@ubuntu.com> Content-Type: text/plain; charset="utf-8"; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 12/19/2014 04:53 PM, Phillip Susi wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On 12/19/2014 4:15 PM, Josef Bacik wrote: >> Please God don't turn off of checksums. Checksums are tracked in >> metadata anyway, they won't show up in the data accounting. Our >> csums are 8 bytes per block, so basic math says you are going to >> max out at 604 megabytes for that big of a file. > > Yes, and it is exactly that metadata space he is complaining about. > So if you don't want to use up all of that space ( and have no use for > the checksums ), then you turn them off. > >> Please people try to only take advice from people who know what >> they are talking about. So unless it's from somebody who has >> commits in btrfs/btrfs-progs take their feedback with a grain of >> salt. Thanks, > > Well that is rather arrogant and rude. For that matter, I *do* have > commits in btrfs-progs. > root@destiny ~/btrfs-progs# git log --oneline --author="Phillip Susi" c65345d btrfs-progs: document --rootdir mkfs switch f6b6e93 btrfs-progs: removed extraneous whitespace from mkfs man page Sorry I should have qualified that statement better. So unless it's from somebody who has had commits to meaningful portions of btrfs/btrfs-progs take their feedback with a grain of salt. There are too many people on this list who give random horribly wrong advice to users that can result in data loss or corruption. Now I'll admit I read her question wrong so what you said wasn't incorrect, I'm sorry for that. I've seen a lot of people responding to questions recently that I don't recognize that have been completely full of crap, I just assumed you were in that camp as well. Thanks, Josef