From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zps78.corp.google.com (zps78.corp.google.com [172.25.146.78]) by smtp-out.google.com with ESMTP id m0GItTWT023101 for ; Wed, 16 Jan 2008 10:55:29 -0800 Received: from py-out-1112.google.com (pybp76.prod.google.com [10.34.92.76]) by zps78.corp.google.com with ESMTP id m0GIsUxK014640 for ; Wed, 16 Jan 2008 10:55:28 -0800 Received: by py-out-1112.google.com with SMTP id p76so647243pyb.2 for ; Wed, 16 Jan 2008 10:55:28 -0800 (PST) Message-ID: <532480950801161055u4191ef1ak644dd4528ab60f8@mail.gmail.com> Date: Wed, 16 Jan 2008 10:55:28 -0800 From: "Michael Rubin" Subject: Re: [patch] Converting writeback linked lists to a tree based data structure In-Reply-To: <400452490.28636@ustc.edu.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080115080921.70E3810653@localhost> <1200386774.15103.20.camel@twins> <532480950801150953g5a25f041ge1ad4eeb1b9bc04b@mail.gmail.com> <400452490.28636@ustc.edu.cn> Sender: owner-linux-mm@kvack.org Return-Path: To: Fengguang Wu Cc: Peter Zijlstra , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Jan 15, 2008 7:01 PM, Fengguang Wu wrote: > Basically I think rbtree is an overkill to do time based ordering. > Sorry, Michael. But s_dirty would be enough for that. Plus, s_more_io > provides fair queuing between small/large files, and s_more_io_wait > provides waiting mechanism for blocked inodes. I think the flush_tree (which is a little more than just an rbtree) provides the same queuing mechanisms that the three or four lists heads do and manages to do it in one structure. The i_flushed_when provides the ability to have blocked inodes wait their turn so to speak. Another motivation behind the rbtree patch is to unify the data structure that handles the priority and mechanism of how we write out the pages of the inodes. There are some ideas about introducing priority schemes for QOS and such in the future. I am not saying this patch is about making that happen, but the idea is to if possible unify the four stages of lists into a single structure to facilitate efforts like that. mrubin -- 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/ . Don't email: email@kvack.org