Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753452AbaFDPKY (ORCPT ); Wed, 4 Jun 2014 11:10:24 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:34575 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751510AbaFDPKV (ORCPT ); Wed, 4 Jun 2014 11:10:21 -0400 Date: Wed, 4 Jun 2014 08:10:20 -0700 From: Christoph Hellwig To: Jens Axboe Cc: Christoph Hellwig , Shaohua Li , linux-kernel@vger.kernel.org Subject: Re: [patch]blk-mq: blk_mq_tag_to_rq should handle flush request Message-ID: <20140604151020.GA13586@infradead.org> References: <20140510040023.GA13788@kernel.org> <5388912F.7010609@kernel.dk> <20140604111133.GA7826@infradead.org> <538F2A11.4060800@kernel.dk> <20140604142012.GA20056@infradead.org> <538F331F.60101@kernel.dk> <20140604145803.GA7826@infradead.org> <538F34FB.7050003@kernel.dk> <20140604150508.GA21551@infradead.org> <538F365C.8050604@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <538F365C.8050604@kernel.dk> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 04, 2014 at 09:08:12AM -0600, Jens Axboe wrote: > >The performance regression is caused by "blk-mq: avoid code > >duplication", but I don't really understand why yet. > > Gah, looks like this one dropped the tag idling. I bet that is why. Ah, thanks. It's indeed exactly the same sort of slow down I bisected back then, this should have rung a bell instead of keeping me occupied for hours.. -- 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/