From: "Amir G." Subject: Re: [PATCH v1 00/30] Ext4 snapshots Date: Tue, 21 Jun 2011 14:06:16 +0300 Message-ID: References: <1307459283-22130-1-git-send-email-amir73il@users.sourceforge.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ext4 Developers List To: Theodore Tso Return-path: Received: from mail-ww0-f42.google.com ([74.125.82.42]:53538 "EHLO mail-ww0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754529Ab1FULGS convert rfc822-to-8bit (ORCPT ); Tue, 21 Jun 2011 07:06:18 -0400 Received: by wwg11 with SMTP id 11so131134wwg.1 for ; Tue, 21 Jun 2011 04:06:17 -0700 (PDT) In-Reply-To: <1307459283-22130-1-git-send-email-amir73il@users.sourceforge.net> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Tue, Jun 7, 2011 at 6:07 PM, wrote= : > Hi All, > > I am resending the snapshots patch series as per Lukas's request. > This time, the snapshot*.c files have not been omitted, as in > the previous posting. > > The series is still based on ext4 dev branch sometime in the preparat= ion > for 3.0 merge window. It was not yet rebased on 3.0-rc1, so punch hol= es > changes have not been addressed yet. > > As always, I advocate online review of the patches at: > https://github.com/amir73il/ext4-snapshots/commits/for-ext4-v1 > but if you insist on doing it the old way, I won't complain. > > Thanks, > Amir. > Hi Ted, To answer your question about possible diet to snapshot patches, following are some diffstat on groups of patches (by functionality). The diffsstat includes only ext4 core file (excluding new snapshot* fil= es). As you can see, removing the shrink/merge functionality for multiple snapshots, will remove the need for exclude bitmap and reduce the chang= es to core files by ~300 insertions. There is some advantage of not having to add the exclude bitmap to exis= ting fs, but I think the win is not so big, assuming that we will want to ha= ve the shrink/merge functionality eventually. Cheers, Amir. > [PATCH v1 01/36] ext4: EXT4 snapshots (Experimental) > [PATCH v1 02/36] ext4: snapshot debugging support Generic stuff. 15 files changed, 122 insertions(+), 1 deletions(-) > [PATCH v1 03/36] ext4: snapshot hooks - inside JBD hooks > [PATCH v1 04/36] ext4: snapshot hooks - block bitmap access > [PATCH v1 05/36] ext4: snapshot hooks - delete blocks > [PATCH v1 06/36] ext4: snapshot hooks - move data blocks > [PATCH v1 07/36] ext4: snapshot hooks - direct I/O > [PATCH v1 08/36] ext4: snapshot hooks - move extent file data blocks Most of the code in this group handles MOW. 7 files changed, 550 insertions(+), 68 deletions(-) > [PATCH v1 09/36] ext4: snapshot file > [PATCH v1 10/36] ext4: snapshot file - read through to block device > [PATCH v1 11/36] ext4: snapshot file - permissions > [PATCH v1 12/36] ext4: snapshot file - store on disk > [PATCH v1 13/36] ext4: snapshot file - increase maximum file size lim= it to 16TB Implementation of special snapshot file. 7 files changed, 220 insertions(+), 14 deletions(-) > [PATCH v1 14/36] ext4: snapshot block operations > [PATCH v1 15/36] ext4: snapshot block operation - copy blocks to snap= shot > [PATCH v1 16/36] ext4: snapshot block operation - move blocks to snap= shot > [PATCH v1 17/36] ext4: snapshot block operation - copy block bitmap t= o snapshot Copy/move to snapshot file operations. 5 files changed, 126 insertions(+), 24 deletions(-) > [PATCH v1 18/36] ext4: snapshot control > [PATCH v1 19/36] ext4: snapshot control - init new snapshot > [PATCH v1 20/36] ext4: snapshot control - fix new snapshot > [PATCH v1 21/36] ext4: snapshot control - reserve disk space for snap= shot Mostly new code in ioctl.c. 6 files changed, 171 insertions(+), 3 deletions(-) > [PATCH v1 22/36] ext4: snapshot journaled - increase transaction cred= its > [PATCH v1 23/36] ext4: snapshot journaled - implement journal_release= _buffer() > [PATCH v1 24/36] ext4: snapshot journaled - bypass to save credits > [PATCH v1 25/36] ext4: snapshot journaled - cache last COW tid in jou= rnal_head Helper functions to handle extra COW credits. 7 files changed, 284 insertions(+), 31 deletions(-) > [PATCH v1 26/36] ext4: snapshot journaled - trace COW/buffer credits Trace/debug for extra COW credits. 3 files changed, 108 insertions(+), 0 deletions(-) > [PATCH v1 27/36] ext4: snapshot list support > [PATCH v1 28/36] ext4: snapshot list - read through to previous snaps= hot Not much to gain from dropping snapshot list support... 2 files changed, 2 insertions(+), 0 deletions(-) > [PATCH v1 29/36] ext4: snapshot race conditions - concurrent COW bitm= ap operations > [PATCH v1 30/36] ext4: snapshot race conditions - concurrent COW oper= ations > [PATCH v1 31/36] ext4: snapshot race conditions - tracked reads We must handle race conditions. 2 files changed, 32 insertions(+), 0 deletions(-) > [PATCH v1 32/36] ext4: snapshot exclude - the exclude bitmap We do not need the exclude bitmap if we do not shrink/merge snapshots. 5 files changed, 226 insertions(+), 3 deletions(-) > [PATCH v1 33/36] ext4: snapshot cleanup > [PATCH v1 34/36] ext4: snapshot cleanup - shrink deleted snapshots > [PATCH v1 35/36] ext4: snapshot cleanup - merge shrunk snapshots We could support multiple snapshots without shrinking/merging deleted s= napshot, but that means that only disk space of oldest snapshot is reclaimed on = delete. 2 files changed, 74 insertions(+), 22 deletions(-) > [PATCH v1 36/36] ext4: snapshot rocompat - enable rw mount > > =A0fs/ext4/Kconfig =A0 =A0 =A0 =A0 =A0 | =A0 11 + > =A0fs/ext4/Makefile =A0 =A0 =A0 =A0 =A0| =A0 =A03 + > =A0fs/ext4/balloc.c =A0 =A0 =A0 =A0 =A0| =A0132 +++ > =A0fs/ext4/ext4.h =A0 =A0 =A0 =A0 =A0 =A0| =A0188 ++++- > =A0fs/ext4/ext4_jbd2.c =A0 =A0 =A0 | =A0162 ++++- > =A0fs/ext4/ext4_jbd2.h =A0 =A0 =A0 | =A0266 ++++++- > =A0fs/ext4/extents.c =A0 =A0 =A0 =A0 | =A0157 ++++- > =A0fs/ext4/file.c =A0 =A0 =A0 =A0 =A0 =A0| =A0 11 +- > =A0fs/ext4/ialloc.c =A0 =A0 =A0 =A0 =A0| =A0 19 +- > =A0fs/ext4/inode.c =A0 =A0 =A0 =A0 =A0 | =A0668 +++++++++++++-- > =A0fs/ext4/ioctl.c =A0 =A0 =A0 =A0 =A0 | =A0120 +++ > =A0fs/ext4/mballoc.c =A0 =A0 =A0 =A0 | =A0161 ++++- > =A0fs/ext4/move_extent.c =A0 =A0 | =A0 =A03 +- > =A0fs/ext4/namei.c =A0 =A0 =A0 =A0 =A0 | =A0 =A09 + > =A0fs/ext4/resize.c =A0 =A0 =A0 =A0 =A0| =A0 19 +- > =A0fs/ext4/snapshot.c =A0 =A0 =A0 =A0| 1000 ++++++++++++++++++++++ > =A0fs/ext4/snapshot.h =A0 =A0 =A0 =A0| =A0690 ++++++++++++++++ > =A0fs/ext4/snapshot_buffer.c | =A0393 +++++++++ > =A0fs/ext4/snapshot_ctl.c =A0 =A0| 2002 +++++++++++++++++++++++++++++= ++++++++++++++++ > =A0fs/ext4/snapshot_debug.c =A0| =A0107 +++ > =A0fs/ext4/snapshot_debug.h =A0| =A0105 +++ > =A0fs/ext4/snapshot_inode.c =A0| =A0960 ++++++++++++++++++++++ > =A0fs/ext4/super.c =A0 =A0 =A0 =A0 =A0 | =A0157 ++++- > =A0fs/ext4/xattr.c =A0 =A0 =A0 =A0 =A0 | =A0 =A04 +- > =A024 files changed, 7182 insertions(+), 165 deletions(-) > > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html