From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp2.belwue.de ([129.143.2.15]:46281 "EHLO smtp2.belwue.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751015AbcK1AjZ (ORCPT ); Sun, 27 Nov 2016 19:39:25 -0500 Received: from fex.rus.uni-stuttgart.de (fex.rus.uni-stuttgart.de [129.69.1.129]) by smtp2.belwue.de with SMTP id uAS0cTA6015516 for ; Mon, 28 Nov 2016 01:38:30 +0100 (MET) env-from (framstag@rus.uni-stuttgart.de) Date: Mon, 28 Nov 2016 01:38:29 +0100 From: Ulli Horlacher To: linux-btrfs@vger.kernel.org Subject: Re: mount option nodatacow for VMs on SSD? Message-ID: <20161128003829.GD15348@rus.uni-stuttgart.de> References: <20161125082840.GA32711@rus.uni-stuttgart.de> <20161126112710.6aca8bac@jupiter.sol.kaishome.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20161126112710.6aca8bac@jupiter.sol.kaishome.de> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Sat 2016-11-26 (11:27), Kai Krakow wrote: > > I have vmware and virtualbox VMs on btrfs SSD. > As a side note: I don't think you can use "nodatacow" just for one > subvolume while the other subvolumes of the same btrfs are mounted > different. The wiki is just wrong here. > > The list of possible mount options in the wiki explicitly lists > "nodatacow" as not working per subvolume - just globally for the whole > fs. Thanks for pointing this out! I have misunderstood this, first. Ok, then next question :-) What is better (for a single user workstation): using mount option "autodefrag" or call "btrfs filesystem defragment -r" (-t ?) via nightly cronjob? So far, I use neither. -- Ullrich Horlacher Server und Virtualisierung Rechenzentrum TIK Universitaet Stuttgart E-Mail: horlacher@tik.uni-stuttgart.de Allmandring 30a Tel: ++49-711-68565868 70569 Stuttgart (Germany) WWW: http://www.tik.uni-stuttgart.de/ REF:<20161126112710.6aca8bac@jupiter.sol.kaishome.de>