Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755514Ab2HXO6j (ORCPT ); Fri, 24 Aug 2012 10:58:39 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:38188 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753038Ab2HXO6g (ORCPT ); Fri, 24 Aug 2012 10:58:36 -0400 Message-ID: <1345820311.4824.2.camel@edumazet-laptop> Subject: Re: [PATCH] fs/proc: Move kfree outside pde_unload_lock From: Eric Dumazet To: Nathan Zimmer Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, adobriyan@gmail.com, Alexander Viro , David Woodhouse Date: Fri, 24 Aug 2012 16:58:31 +0200 In-Reply-To: <20120824144852.GA18850@gulag1.americas.sgi.com> References: <1345653510-22000-1-git-send-email-nzimmer@sgi.com> <1345660110.5158.1969.camel@edumazet-glaptop> <1345671778.5158.2369.camel@edumazet-glaptop> <20120824144852.GA18850@gulag1.americas.sgi.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 8bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1243 Lines: 44 Le vendredi 24 août 2012 à 09:48 -0500, Nathan Zimmer a écrit : > On Wed, Aug 22, 2012 at 11:42:58PM +0200, Eric Dumazet wrote: > > On Wed, 2012-08-22 at 20:28 +0200, Eric Dumazet wrote: > > > > > > > > Thats interesting, but if you really want this to fly, one RCU > > > conversion would be much better ;) > > > > > > pde_users would be an atomic_t and you would avoid the spinlock > > > contention. > > > > Here is what I had in mind, I would be interested to know how it helps a 512 core machine ;) > > > > Here are the results and they look great. > > cpuinfo baseline moved kfree Rcu > tasks read-sec read-sec read-sec > 1 0.0141 0.0141 0.0141 > 2 0.0140 0.0140 0.0142 > 4 0.0140 0.0141 0.0141 > 8 0.0145 0.0145 0.0140 > 16 0.0553 0.0548 0.0168 > 32 0.1688 0.1622 0.0549 > 64 0.5017 0.3856 0.1690 > 128 1.7005 0.9710 0.5038 > 256 5.2513 2.6519 2.0804 > 512 8.0529 6.2976 3.0162 > > > Indeed... Could you explicit the test you are actually doing ? Thanks -- 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/