Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755809Ab2HXOtJ (ORCPT ); Fri, 24 Aug 2012 10:49:09 -0400 Received: from relay1.sgi.com ([192.48.179.29]:46702 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753571Ab2HXOtH (ORCPT ); Fri, 24 Aug 2012 10:49:07 -0400 Date: Fri, 24 Aug 2012 09:48:52 -0500 From: Nathan Zimmer To: Eric Dumazet Cc: Nathan Zimmer , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, adobriyan@gmail.com, Alexander Viro , David Woodhouse Subject: Re: [PATCH] fs/proc: Move kfree outside pde_unload_lock Message-ID: <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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1345671778.5158.2369.camel@edumazet-glaptop> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1041 Lines: 35 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 -- 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/