From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from meiko.romanrm.net ([195.154.92.155]:38239 "EHLO meiko.romanrm.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751668AbbGIPEn (ORCPT ); Thu, 9 Jul 2015 11:04:43 -0400 Date: Thu, 9 Jul 2015 20:04:41 +0500 From: Roman Mamedov To: Austin S Hemmelgarn Cc: sander@humilis.net, "Fajar A. Nugraha" , james harvey , linux-btrfs Subject: Re: btrfs subvolume clone or fork (btrfs-progs feature request) Message-ID: <20150709200441.111e3d64@natsu> In-Reply-To: <559E6D80.7010607@gmail.com> References: <559E6411.6090109@gmail.com> <20150709124121.GA25033@panda> <559E6D80.7010607@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/VwI97jRwithwgKNusth0Yx."; protocol="application/pgp-signature" Sender: linux-btrfs-owner@vger.kernel.org List-ID: --Sig_/VwI97jRwithwgKNusth0Yx. Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Thu, 09 Jul 2015 08:48:00 -0400 Austin S Hemmelgarn wrote: > On 2015-07-09 08:41, Sander wrote: > > Austin S Hemmelgarn wrote (ao): > >>> What's wrong with "btrfs subvolume snapshot"? > >> > >> Well, personally I would say the fact that once something is tagged as > >> a snapshot, you can't change it to a regular subvolume without doing a > >> non-incremental send/receive. > > > > A snapshot is a subvolume. There is no such thing as "tagged as a > > snapshot". > > > > Sander > > > No, there is a bit in the subvolume metadata that says whether it's=20 > considered a snapshot or not. Internally, they are handled identically,= =20 > but it does come into play when you consider things like btrfs subvolume= =20 > show -s (which only lists snapshots), which in turn means that certain=20 > tasks are more difficult to script robustly. This sounds like a vestigial leftover from back when snapshots were conceptualized to be somehow functionally different from subvolumes... But = as you said, now there is effectively no difference, so that bit is used for what, only to track how a subvolume was created? And to output in the subvolume list if the user passes "-s"? I'd say that's a pretty oddball fea= ture to even have, since in any case if you want to distinguish and list only yo= ur snapshots, you would typically just name them in a certain way, e.g. "/snaps/originalname/". --=20 With respect, Roman --Sig_/VwI97jRwithwgKNusth0Yx. Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEYEARECAAYFAlWejYkACgkQTLKSvz+PZwgrtgCgg0Y6jBpXeiQfWGnr/7ap0Yah QRwAoIMiw8U1He0do3XxwVXSWWggs4n5 =JaYP -----END PGP SIGNATURE----- --Sig_/VwI97jRwithwgKNusth0Yx.--