From patchwork Mon Jul 25 02:33:15 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anton Blanchard X-Patchwork-Id: 106655 X-Patchwork-Delegate: benh@kernel.crashing.org Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [IPv6:::1]) by ozlabs.org (Postfix) with ESMTP id 61ED7B8219 for ; Mon, 25 Jul 2011 22:37:58 +1000 (EST) Received: from localhost (ppp121-44-26-110.lns20.syd6.internode.on.net [121.44.26.110]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPSA id B3684B721E; Mon, 25 Jul 2011 22:37:23 +1000 (EST) X-Mailbox-Line: From anton@samba.org Mon Jul 25 12:34:26 2011 Message-Id: <20110725023426.307093692@samba.org> User-Agent: quilt/0.48-1 Date: Mon, 25 Jul 2011 12:33:15 +1000 From: Anton Blanchard To: mingo@elte.hu, peterz@infradead.org, benh@kernel.crashing.org Subject: [PATCH 4/5] powerpc/numa: Disable NEWIDLE balancing at node level References: <20110725023311.175792493@samba.org> Content-Disposition: inline; filename=nodes_no_newidle Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org On big POWER7 boxes we see large amounts of CPU time in system processes like workqueue and watchdog kernel threads. We currently rebalance the entire machine each time a task goes idle and this is very expensive on large machines. Disable newidle balancing at the node level and rely on the scheduler tick to rebalance across nodes. Signed-off-by: Anton Blanchard Index: linux-2.6-work/arch/powerpc/include/asm/topology.h =================================================================== --- linux-2.6-work.orig/arch/powerpc/include/asm/topology.h 2011-07-25 12:14:25.448671947 +1000 +++ linux-2.6-work/arch/powerpc/include/asm/topology.h 2011-07-25 12:14:26.568692651 +1000 @@ -75,7 +75,7 @@ static inline int pcibus_to_node(struct .forkexec_idx = 0, \ \ .flags = 1*SD_LOAD_BALANCE \ - | 1*SD_BALANCE_NEWIDLE \ + | 0*SD_BALANCE_NEWIDLE \ | 1*SD_BALANCE_EXEC \ | 1*SD_BALANCE_FORK \ | 0*SD_BALANCE_WAKE \