From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out2-smtp.messagingengine.com ([66.111.4.26]:57556 "EHLO out2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756002AbaISQvQ (ORCPT ); Fri, 19 Sep 2014 12:51:16 -0400 Received: from compute6.internal (compute6.nyi.internal [10.202.2.46]) by gateway2.nyi.internal (Postfix) with ESMTP id 9E94320132 for ; Fri, 19 Sep 2014 12:51:15 -0400 (EDT) Received: from [192.168.0.10] (unknown [87.115.91.188]) by mail.messagingengine.com (Postfix) with ESMTPA id 3998DC00919 for ; Fri, 19 Sep 2014 12:51:15 -0400 (EDT) Message-ID: <1411145469.1601.2.camel@zarniwoop.blob> Subject: Re: Performance Issues From: Rob Spanton Reply-To: rob@robspanton.com To: linux-btrfs@vger.kernel.org Date: Fri, 19 Sep 2014 17:51:09 +0100 In-Reply-To: <541C464F.3030600@fb.com> References: <1411129114.1811.7.camel@zarniwoop.blob> <541C464F.3030600@fb.com> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-XVWPZCpJlg5zwxbNSWPW" Mime-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: --=-XVWPZCpJlg5zwxbNSWPW Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi, Thanks for the response everyone. I wrote: > I have a particularly uncomplicated setup (a desktop PC with a hard > disk) and I'm seeing particularly slow performance from btrfs. A `git > status` in the linux source tree takes about 46 seconds after dropping > caches, whereas on other machines using ext4 this takes about 13s. My > mail client (evolution) also seems to perform particularly poorly on > this setup, and my hunch is that it's spending a lot of time waiting on > the filesystem. The evolution problem has been improved: the sqlite db that it was using had over 18000 fragments, so I got evolution to recreate that file with nocow set. It now takes "only" 30s to load my mail rather than 80s, which is better... On Fri, 2014-09-19 at 11:05 -0400, Josef Bacik wrote: > Weird, I get the exact opposite performance. Anyway it's probably=20 > because of your file layouts, try defragging your git dir and see if=20 > that helps. Thanks, Defragging has improved matters a bit: it now takes 26s (was 46s) to run git status. Still not amazing, but at the moment I have no evidence to suggest that it's not something to do with the machine's hardware. If I get time over the weekend I'll dig out an external hard disk and try a couple of benchmarks with that. For reference, these are the mount flags: /dev/sda4 on / type btrfs (rw,noatime,space_cache) /dev/sda4 on /home type btrfs (rw,noatime,space_cache) Cheers, Rob --=-XVWPZCpJlg5zwxbNSWPW Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABAgAGBQJUHF8CAAoJELnJXuxeMxduav8P/1qSndNoBiMegfoQjvj4it1r RVvk8hXQdJnBrIankA8L8cTFV5uof8JVpcewwrI0bwZeVfcSN+vx1PTMF7aH2An5 YaYofOHGf5lPVA5SDb8mBaRwyV5krmXNNsJnT0g1jRrVRjuxN/gGGCt0yqzs4cdF k0kX9APhjpiVZZpNhF1FU58JtAO+lxbBBR2AA6YjLjLH5jw1nF7A87O+3GlMKTnR ZIUypL8vQFaxAtaTDnwi0lBQeDkr4oIUjdggEum/R/9dZtmDzOoqnL7EDP68Jon6 qWBQszxaAAsvbhgViv8p6WC7Qs6Sfd7E5u6F1o85CjxZnGVsR2zLcqQdfeitnfkT yjOILjefHgMtUoAdWmhmKt2gSypilD27VwLe8+wzVy0aYeHbWE7swnkwUmuJC3O7 I41AP2ty37V8zv4MC39cJvNBmNk74HLtZX6wSd9cPPKrUbf/2SOc08vJRHMIX/Ka Hcv/mmlOPPi9OdZ6Z4wRFnW8grgMF24tqBJkeWwIytpP6dsTJ+F35eSIfBEmLfv+ JTZPBqfkajX5XxiuAHZcMMHVNNKCJsBug4MqBiE98zqXcE5CR3RKEDODgaaCgRrv c/xhKDy+NO5Ng2rW6LFNDE3db/SyVXHu8PlCyfd/GU4hQAJ6PCdb36hWMDpveQ9C 2WferktJc6Vx1vQWYxbN =3TWx -----END PGP SIGNATURE----- --=-XVWPZCpJlg5zwxbNSWPW--