Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752819AbXJ3ENi (ORCPT ); Tue, 30 Oct 2007 00:13:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752727AbXJ3ENU (ORCPT ); Tue, 30 Oct 2007 00:13:20 -0400 Received: from note.orchestra.cse.unsw.EDU.AU ([129.94.242.24]:60933 "EHLO note.orchestra.cse.unsw.EDU.AU" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752187AbXJ3ENT (ORCPT ); Tue, 30 Oct 2007 00:13:19 -0400 From: Aaron Carroll To: Jens Axboe Date: Tue, 30 Oct 2007 15:05:46 +1100 X-Spam-Score: 0.001 X-CSE-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on note.orchestra.cse.unsw.EDU.AU X-CSE-Spam-Level: X-CSE-Spam-Status: No, score=-2.6 required=4.0 tests=BAYES_00,UNPARSEABLE_RELAY autolearn=ham version=3.1.3 Message-ID: <4726AD9A.8040707@gelato.unsw.edu.au> User-Agent: Thunderbird 2.0.0.6 (X11/20070803) MIME-Version: 1.0 CC: linux-kernel@vger.kernel.org, Peter Chubb Subject: [PATCH 2/3] Deadline iosched: Reset batch for ordered requests References: <4726AD03.2080908@gelato.unsw.edu.au> In-Reply-To: <4726AD03.2080908@gelato.unsw.edu.au> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1784 Lines: 51 The deadline I/O scheduler does not reset the batch count when starting a new batch at a higher-sectored request. This means the second and subsequent batch in the same data direction will never exceed a single request in size whenever higher-sectored requests are pending. This patch gives new batches in the same data direction as old ones their full quota of requests by resetting the batch count. Signed-off-by: Aaron Carroll --- block/deadline-iosched.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c index a44437e..cb94c83 100644 --- a/block/deadline-iosched.c +++ b/block/deadline-iosched.c @@ -306,12 +306,11 @@ dispatch_writes: dispatch_find_request: /* * we are not running a batch, find best request for selected data_dir + * and start a new batch */ if (deadline_check_fifo(dd, data_dir)) { /* An expired request exists - satisfy it */ - dd->batching = 0; rq = rq_entry_fifo(dd->fifo_list[data_dir].next); - } else if (dd->next_rq[data_dir]) { /* * The last req was the same dir and we have a next request in @@ -325,12 +324,13 @@ dispatch_find_request: * higher-sectored requests. Go back to the lowest sectored * request (1 way elevator) and start a new batch. */ - dd->batching = 0; node = rb_first(&dd->sort_list[data_dir]); if (node) rq = rb_entry_rq(node); } + dd->batching = 0; + dispatch_request: /* * rq is the selected appropriate request. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/