From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mondschein.lichtvoll.de ([194.150.191.11]:49994 "EHLO mail.lichtvoll.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752015AbaCILyQ (ORCPT ); Sun, 9 Mar 2014 07:54:16 -0400 From: Martin Steigerwald To: Hugo Mills , =?ISO-8859-1?Q?Sw=E2mi?= Petaramesh , linux-btrfs@vger.kernel.org Subject: Re: Massive BTRFS performance degradation Date: Sun, 09 Mar 2014 12:54:08 +0100 Message-ID: <2387882.QV4t13Wz0H@merkaba> In-Reply-To: <20140309113350.GH6318@carfax.org.uk> References: <531C1CC4.701@gmail.com> <1756989.4ep0Vdupld@tethys> <20140309113350.GH6318@carfax.org.uk> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart8719138.rLpX7DvT87"; micalg="pgp-sha1"; protocol="application/pgp-signature" Sender: linux-btrfs-owner@vger.kernel.org List-ID: --nextPart8719138.rLpX7DvT87 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" Am Sonntag, 9. M=E4rz 2014, 11:33:50 schrieb Hugo Mills: > On Sun, Mar 09, 2014 at 11:23:29AM +0100, Sw=E2mi Petaramesh wrote: > > Le dimanche 9 mars 2014 11:01:17 vous avez =E9crit : > > > This ThinkPad T520 has been with BTRFS since installation of the = Debian > > > sid system on it with Kernel 2.6.39 or even 2.6.38 (where Sandybr= idge > > > graphics didn=B4t work so well as today yet). > > >=20 > > > So that much to any FUD about BTRFS and SSDs. > > > >=20 > > > > Wow ! > > > >=20 > > > > Thanks for this very interesting info. Would you tell me if you use= any of > > the SSD optimisation mount options: discard, ssd or ssd_spread ? >=20 > I would recommend none of the three. >=20 > ssd should be activated automatically on any non-rotational device= . > ssd_spread is generally slower on modern SSDs than the ssd option. > discard is, except on the very latest hardware, a synchronous command= > (it's a limitation of the SATA standard), and therefore results in > very very poor performance. Thats exactly how I use it. I just fstrim the partitions from time to t= ime. Thanks, =2D-=20 Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7 --nextPart8719138.rLpX7DvT87 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) iEYEABECAAYFAlMcVmYACgkQmRvqrKWZhMf5sQCfdyJ0noIfFw24N4wLUDAlujwI Gg8AnjHDZxA7ZnsO+ThWUO1Whj9060bO =tz99 -----END PGP SIGNATURE----- --nextPart8719138.rLpX7DvT87--