From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id 3A41F900086 for ; Mon, 18 Apr 2011 08:29:28 -0400 (EDT) Subject: Re: [PATCH 1/1] Add check for dirty_writeback_interval in bdi_wakeup_thread_delayed From: Artem Bityutskiy Reply-To: Artem.Bityutskiy@nokia.com In-Reply-To: <20110418091609.GC5143@Xye> References: <20110417162308.GA1208@Xye> <1303111152.2815.29.camel@localhost> <20110418091609.GC5143@Xye> Content-Type: text/plain; charset="UTF-8" Date: Mon, 18 Apr 2011 15:26:29 +0300 Message-ID: <1303129589.8589.5.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Raghavendra D Prabhu Cc: linux-mm@kvack.org, Jens Axboe , Christoph Hellwig , Andrew Morton , linux-kernel@vger.kernel.org On Mon, 2011-04-18 at 14:46 +0530, Raghavendra D Prabhu wrote: > I have set it to 500 centisecs as that is the default value of > dirty_writeback_interval. I used this logic for following reason: the > purpose for which dirty_writeback_interval is set to 0 is to disable > periodic writeback > (http://tomoyo.sourceforge.jp/cgi-bin/lxr/source/fs/fs-writeback.c#L818) > , whereas here (in bdi_wakeup_thread_delayed) it is being used for a > different purpose -- to delay the bdi wakeup in order to reduce context > switches for dirty inode writeback. But why it wakes up the bdi thread? Exactly to make sure the periodic write-back happen. -- Best Regards, Artem Bityutskiy (D?N?N?N?D 1/4 D?D,N?N?N?DoD,D1) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org