From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.17.22]:52241 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751498AbaITIX7 (ORCPT ); Sat, 20 Sep 2014 04:23:59 -0400 From: Marc Dietrich To: Holger =?ISO-8859-1?Q?Hoffst=E4tte?= Cc: linux-btrfs@vger.kernel.org Subject: Re: Performance Issues Date: Sat, 20 Sep 2014 10:23:52 +0200 Message-ID: <1678306.dObPo7E7s7@fb07-iapwap2> In-Reply-To: References: <1411129114.1811.7.camel@zarniwoop.blob> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart10776813.lzMSiVhkQ7"; micalg="pgp-sha1"; protocol="application/pgp-signature" Sender: linux-btrfs-owner@vger.kernel.org List-ID: --nextPart10776813.lzMSiVhkQ7 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="UTF-8" Am Freitag, 19. September 2014, 13:51:22 schrieb Holger Hoffst=C3=A4tte= : >=20 > On Fri, 19 Sep 2014 13:18:34 +0100, Rob Spanton wrote: >=20 > > 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 dropp= ing > > caches, whereas on other machines using ext4 this takes about 13s. = My > > mail client (evolution) also seems to perform particularly poorly o= n > > this setup, and my hunch is that it's spending a lot of time waitin= g on > > the filesystem. >=20 > This is - unfortunately - a particular btrfs oddity/characteristic/fl= aw, > whatever you want to call it. git relies a lot on fast stat() calls, > and those seem to be particularly slow with btrfs esp. on rotational > media. I have the same problem with rsync on a freshly mounted volume= ; > it gets fast (quite so!) after the first run. my favorite benchmark is "ls -l /usr/bin": ext4: 0.934s btrfs: 21.814s also mounting large partitons (several 100Gs) takes lot of time on btrf= s. Better to defer it during boot using e.g. "noauto,x-systemd.automount".= Marc --nextPart10776813.lzMSiVhkQ7 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 v2.0.22 (GNU/Linux) iQEcBAABAgAGBQJUHTmYAAoJEKyeR39HFBtoVB4H/R1fL37opgSqmGN8jsM7Kmns dYtbWsYfFS8kDUXNpyRX/e/zxIyVrDWhCiakPFlgFgOj56UCDemhbujUgk9huh4N rLutQppfw4TDqVik0Ae76hcm4RT8NBcG3VdA2zdJrre40A8K9V6n7UAFD15xXMKl SwsGAhv/02zSvnpFBWnCGKTYVc+1A9ydbqgddwiOgyyXhRqiGR20b+RilVVh8ecm qh8GofB+a7sXgeMSVFtbeqZHVgWkAsL/xrCkcBB8cb/kmht5U3OqnArb77QJqSVl RlzK31u1InKKZbynwv/K4b6JobI9Jo0d29bxumFuMIP0fkHTQaXeXZ0mglHQphw= =2n0B -----END PGP SIGNATURE----- --nextPart10776813.lzMSiVhkQ7--