From: Artem Bityutskiy Subject: [PATCH v1 0/8] do not use s_dirt in ext2 Date: Wed, 21 Mar 2012 18:14:27 +0200 Message-ID: <1332346475-1441-1-git-send-email-dedekind1@gmail.com> Cc: Ext4 Mailing List , Linux FS Maling List , Linux Kernel Maling List To: Jan Kara Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org This patch-set makes ext2 independent of the VFS superblock management services. Namely, ext2 does not require to register the 'write_super()' VFS call-back. The reason of this exercises is to get rid of the 'sync_supers()' kernel thread which wakes up every 5 seconds (by default) even if all superblocks are clean. This is wasteful from power management POW (unnecessary wake-ups). Note, I tried to optimize 'sync_supers()' instead in 2010, but Al wanted me to get rid of it instead. See https://lkml.org/lkml/2010/6/6/87 And I think this is right because many file-systems do not need this, for example btrfs does not use VFS superblock management services at all, so on a btrfs-based system we currently end-up useless periodic wake-ups source. I have sent a similar patch-set for ext4 recently to Ted, see: http://lkml.org/lkml/2012/3/20/220 Changes for other file-systems are coming later. The patch-set structure. 1. patch 1 exports 'dirty_writeback_interval' and I also sent it as part of the ext4 patch-set 2. patch 2 is also and independent VFS clean-up and I also sent it as part of the ext4 patch-set 3. patch 3 is an independent ext2 clean-up patch 4. patches 4-8 actually make ext2 independent on the 'sync_supers()' thread. Thanks, Artem.