From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from frost.carfax.org.uk ([85.119.82.111]:54403 "EHLO frost.carfax.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752195Ab3J0URx (ORCPT ); Sun, 27 Oct 2013 16:17:53 -0400 Date: Sun, 27 Oct 2013 20:17:50 +0000 From: Hugo Mills To: Lester B Cc: linux-btrfs@vger.kernel.org Subject: Re: Total fs size does not match with the actual size of the setup Message-ID: <20131027201750.GG31029@carfax.org.uk> References: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="FwyhczKCDPOVeYh6" In-Reply-To: Sender: linux-btrfs-owner@vger.kernel.org List-ID: --FwyhczKCDPOVeYh6 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Oct 28, 2013 at 04:09:18AM +0800, Lester B wrote: > The btrfs setup only have one device of size 7 GiB but > when I run df, the total size shown is 15 GiB. Running > btrfs --repair I'd recommend not running btrfs check --repair unless you really know what you're doing, or you've checked with someone knowledgable and they say you should try it. On a non-broken filesystem (as here), it's probably OK, though. > displays an error "cache and super > generation don't match, space cache will be invalidated." This is harmless. > How can I correct the total fs size as shown in df? You can't. It's an artefact of the fact that you've got a RAID-1 (or RAID-10, or --mixed and DUP) filesystem, and that the standard kernel interface for df doesn't allow us to report the correct figures -- see [1] (and the subsequent entry as well) for a more detailed description. Hugo. [1] https://btrfs.wiki.kernel.org/index.php/FAQ#Why_does_df_show_incorrect_free_space_for_my_RAID_volume.3F -- === Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk === PGP key: 65E74AC0 from wwwkeys.eu.pgp.net or http://www.carfax.org.uk --- Nothing right in my left brain. Nothing left in --- my right brain. --FwyhczKCDPOVeYh6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) iQIVAwUBUm107lheFHXiqx3kAQIyRBAAnMmBm6iQCdEMJ7B20F+lb6IpXil46x1a 9Vh/2zY0iBVRJi/cCSvghXSHB088Tg9++d7lHialFVXebmox8BrEwnkOyOX5OqCK jHQ9j49wKuLCV/z0lvLjLQJzJaNd25QJM3gl2fKeLUKHjuWJYWMlkEj4pVFTKSo0 46hbiADgI/BPITUAV284S7SwyX8kYidr1ytPIwsSQlfnan+Nez3+n81oZsHFb6aS 5gwaWQqhX9M3iKgmsqCU0nlpLxQtIwnZgEoTHMWdnkz6tcsi3B+FA5WBneBXzmmu QVGPyz2PLSzHbqLMlGR7hRLnikKFbtJItcRwCP7Y+tvO84FkcBa0usxDIIL20Au7 OVRhn3C3mHuQNMfy4dJUspCE0yZIx7US1TLufzPZiakvq2XEfK7zedX/KAmk8me8 fc0vu1XRsgEvNAsc/c4QBX29y4oYiyA78LFB3QL20FPhD6IgktqQmPc24JqlfVQv CpkIG5utVWkIcFPh+IJRWcRHAmveX3p7jY9j6v1C/aetNKW9KIW5HO5R5hDxeu7k Cm5Y54g6i/YYgsvW/Tw5L1lduG5tUT0b0OtV2gHWFVKa7YoQuwXSwQGAXz6a2eMi LNeNqvk9j3w+gfRuXx/0/k6nsa7e+ANUK7hzqP0VqXAWnFUymbaRhy1axAGPGi1Z LSsrcpyswW8= =cQgm -----END PGP SIGNATURE----- --FwyhczKCDPOVeYh6--