From owner-freebsd-fs@FreeBSD.ORG Wed Nov 19 01:36:18 2014 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 192F6815 for ; Wed, 19 Nov 2014 01:36:18 +0000 (UTC) Received: from mail-pd0-x231.google.com (mail-pd0-x231.google.com [IPv6:2607:f8b0:400e:c02::231]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id D66FE1B2 for ; Wed, 19 Nov 2014 01:36:17 +0000 (UTC) Received: by mail-pd0-f177.google.com with SMTP id ft15so3566622pdb.22 for ; Tue, 18 Nov 2014 17:36:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=jU0yGwi1VlRTBW0YOpssLzWk4ee1KiPIdvF72UaVqo0=; b=o9esrpbdMRJY1Zb7aQiTOUXIr1qSPLVSmsP8E3qZjqICLoplEBPDzUbN2JxFEVApoa f1QIyxPJ8XY2Ds9+WL/ksdoS1bAVQl0MFIvNUtSRHdORfB9XgTM85PTwY+jIf81YWcR5 X/P+3bea6OyQKIAgtjEKFw63KJIlsikkx1l6sYqfUCP/ItA15p/Oia9holsggvLuCjyI MXB1cdmpXsT59nWb5jYIzsnWcsn36pBoG0D+ZHXrQLPKeBCpl7oZFOXskQIV7cCMP3sg DaMTnR8OVMLdduSgKusGAyD6YBnzH5IzcbGlweKILa4sO/6a5c9aKmLpmyKjChmsTM6A nCpQ== X-Received: by 10.67.6.1 with SMTP id cq1mr13001408pad.23.1416360977376; Tue, 18 Nov 2014 17:36:17 -0800 (PST) Received: from core.summit (2001-44b8-31c7-e401-4a5b-39ff-fe76-f665.static.ipv6.internode.on.net. [2001:44b8:31c7:e401:4a5b:39ff:fe76:f665]) by mx.google.com with ESMTPSA id s5sm106045pdc.52.2014.11.18.17.36.14 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 18 Nov 2014 17:36:16 -0800 (PST) Date: Wed, 19 Nov 2014 12:36:11 +1100 From: Emil Mikulic To: d@delphij.net Subject: Re: No more free space after upgrading to 10.1 and zpool upgrade Message-ID: <20141119013611.GA52102@core.summit> References: <20141116080128.GA20042@exhan.dylanleigh.net> <20141118054443.GA40514@core.summit> <546B8203.5040607@platinum.linux.pl> <546B9754.4060906@delphij.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <546B9754.4060906@delphij.net> User-Agent: Mutt/1.5.23 (2014-03-12) Cc: freebsd-fs@freebsd.org X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Nov 2014 01:36:18 -0000 On Tue, Nov 18, 2014 at 11:00:36AM -0800, Xin Li wrote: > On 11/18/14 09:29, Adam Nowacki wrote: > > This commit is to blame: > > http://svnweb.freebsd.org/base?view=revision&revision=268455 > > > > 3.125% of disk space is reserved. This is the sort of thing I suspected, but I didn't spot this commit. > Note that the reserved space is so that one can always delete files, > etc. to get the pool back to a usable state. What about the "truncate -s0" trick? That doesn't work reliably? > I've added a new tunable/sysctl in r274674, but note that tuning is > not recommended Thanks!! Can you give us an example of how (and when) to tune the sysctl? Regarding r268455, this is kind of a gotcha for people who are running their pools close to full - should this be mentioned in UPDATING or in the release notes? I understand that ZFS needs free space to be able to free more space, but 3% of a large pool is a lot of bytes.