From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o0BBrNDn138152 for ; Mon, 11 Jan 2010 05:53:24 -0600 Received: from mail.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id CA1B11357F87 for ; Mon, 11 Jan 2010 03:54:17 -0800 (PST) Received: from mail.internode.on.net (bld-mail12.adl6.internode.on.net [150.101.137.97]) by cuda.sgi.com with ESMTP id fEcfI6AM2TIPFMwL for ; Mon, 11 Jan 2010 03:54:17 -0800 (PST) Received: from discord (unverified [121.44.168.156]) by mail.internode.on.net (SurgeMail 3.8f2) with ESMTP id 11397740-1927428 for ; Mon, 11 Jan 2010 22:24:16 +1030 (CDT) Received: from [192.168.1.6] (helo=disturbed) by discord with esmtp (Exim 4.69) (envelope-from ) id 1NUIqd-0003fo-GC for xfs@oss.sgi.com; Mon, 11 Jan 2010 22:54:15 +1100 Received: from dave by disturbed with local (Exim 4.71) (envelope-from ) id 1NUImb-0006qd-A3 for xfs@oss.sgi.com; Mon, 11 Jan 2010 22:50:05 +1100 From: Dave Chinner Subject: [PATCH 3/3] XFS: Don't wake xfsbufd when idle Date: Mon, 11 Jan 2010 22:49:59 +1100 Message-Id: <1263210599-25067-4-git-send-email-david@fromorbit.com> In-Reply-To: <1263210599-25067-1-git-send-email-david@fromorbit.com> References: <1263210599-25067-1-git-send-email-david@fromorbit.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com The xfsbufd wakes every xfsbufd_centisecs (once per second by default) for each filesystem even when the filesystem is idle. If the xfsbufd has nothing to do, put it into a long term sleep and only wake it up when there is work pending (i.e. dirty buffers to flush soon). This will make laptop power misers happy. Signed-off-by: Dave Chinner --- fs/xfs/linux-2.6/xfs_buf.c | 20 +++++++++++++++----- 1 files changed, 15 insertions(+), 5 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c index 77b8be8..b51be4e 100644 --- a/fs/xfs/linux-2.6/xfs_buf.c +++ b/fs/xfs/linux-2.6/xfs_buf.c @@ -1595,6 +1595,11 @@ xfs_buf_delwri_queue( list_del(&bp->b_list); } + if (list_empty(dwq)) { + /* start xfsbufd as it is about to have something to do */ + wake_up_process(bp->b_target->bt_task); + } + bp->b_flags |= _XBF_DELWRI_Q; list_add_tail(&bp->b_list, dwq); bp->b_queuetime = jiffies; @@ -1644,6 +1649,8 @@ xfsbufd_wakeup( list_for_each_entry(btp, &xfs_buftarg_list, bt_list) { if (test_bit(XBT_FORCE_SLEEP, &btp->bt_flags)) continue; + if (list_empty(&btp->bt_delwrite_queue)) + continue; set_bit(XBT_FORCE_FLUSH, &btp->bt_flags); wake_up_process(btp->bt_task); } @@ -1708,6 +1715,9 @@ xfsbufd( set_freezable(); do { + long age = xfs_buf_age_centisecs * msecs_to_jiffies(10); + long tout = age; + if (unlikely(freezing(current))) { set_bit(XBT_FORCE_SLEEP, &target->bt_flags); refrigerator(); @@ -1715,12 +1725,12 @@ xfsbufd( clear_bit(XBT_FORCE_SLEEP, &target->bt_flags); } - schedule_timeout_interruptible( - xfs_buf_timer_centisecs * msecs_to_jiffies(10)); - - xfs_buf_delwri_split(target, &tmp, - xfs_buf_age_centisecs * msecs_to_jiffies(10)); + /* sleep for a long time if there is nothing to do. */ + if (list_empty(&target->bt_delwrite_queue)) + tout = MAX_SCHEDULE_TIMEOUT; + schedule_timeout_interruptible(tout); + xfs_buf_delwri_split(target, &tmp, age); count = 0; while (!list_empty(&tmp)) { bp = list_entry(tmp.next, xfs_buf_t, b_list); -- 1.6.5 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs