From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:27408 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752053Ab3LQBTq convert rfc822-to-8bit (ORCPT ); Mon, 16 Dec 2013 20:19:46 -0500 From: Chris Mason To: "dsterba@suse.cz" CC: Josef Bacik , "linux-btrfs@vger.kernel.org" Subject: Re: [PATCH] Btrfs: move the extent buffer radix tree into the fs_info Date: Tue, 17 Dec 2013 01:19:39 +0000 Message-ID: <1387243189.15080.2.camel@ret.masoncoding.com> References: <1387218386-5339-1-git-send-email-jbacik@fb.com> <20131217010627.GK6498@twin.jikos.cz> In-Reply-To: <20131217010627.GK6498@twin.jikos.cz> Content-Type: text/plain; charset="utf-7" MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Tue, 2013-12-17 at 02:06 +-0100, David Sterba wrote: +AD4- On Mon, Dec 16, 2013 at 01:26:26PM -0500, Josef Bacik wrote: +AD4- +AD4- I need to create a fake tree to test qgroups and I don't want to have to setup a +AD4- +AD4- fake btree+AF8-inode. The fact is we only use the radix tree for the fs+AF8-info, so +AD4- +AD4- everybody else who allocates an extent+AF8-io+AF8-tree is just wasting the space anyway. +AD4- +AD4- This patch moves the radix tree and its lock into btrfs+AF8-fs+AF8-info so there is less +AD4- +AD4- stuff I have to fake to do qgroup sanity tests. Thanks, +AD4- +AD4- This would make the fs+AF8-info::buffer+AF8-lock a global hotspot if +AD4- alloc+AF8-extent+AF8-buffer and release+AF8-extent+AF8-buffer are called frequently. +AD4- But since the only place that was really using it was the metadata btree, the lock shouldn't be hotter than before right? -chris