From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935913Ab0B1Soq (ORCPT ); Sun, 28 Feb 2010 13:44:46 -0500 Received: from 0122700014.0.fullrate.dk ([95.166.99.235]:60036 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933331Ab0B1Sop (ORCPT ); Sun, 28 Feb 2010 13:44:45 -0500 Date: Sun, 28 Feb 2010 19:44:44 +0100 From: Jens Axboe To: Corrado Zoccolo Cc: Linux-Kernel , Jeff Moyer , Vivek Goyal , Shaohua Li , Gui Jianfeng Subject: Re: [PATCH] cfq-iosched: requests "in flight" vs "in driver" clarification Message-ID: <20100228184444.GH5768@kernel.dk> References: <1267286589-316-1-git-send-email-czoccolo@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1267286589-316-1-git-send-email-czoccolo@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 27 2010, Corrado Zoccolo wrote: > Counters for requests "in flight" and "in driver" are used asymmetrically > in cfq_may_dispatch, and have slightly different meaning. > We split the rq_in_flight counter (was sync_flight) to count both sync > and async requests, in order to use this one, which is more accurate in > some corner cases. > The rq_in_driver counter is coalesced, since individual sync/async counts > are not used any more. Thanks, applied. -- Jens Axboe