From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Bligh Subject: Re: Scalability of interface creation and deletion Date: Sat, 07 May 2011 19:50:52 +0100 Message-ID: <52426C6458B2FEE35EF69E4A@Ximines.local> References: <891B02256A0667292521A4BF@Ximines.local> <1304770926.2821.1157.camel@edumazet-laptop> <0F4A638C2A523577CDBC295E@Ximines.local> <1304785589.3207.5.camel@edumazet-laptop> <178E8895FB84C07251538EF7@Ximines.local> <1304793174.3207.22.camel@edumazet-laptop> <1304793749.3207.26.camel@edumazet-laptop> Reply-To: Alex Bligh Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, Alex Bligh To: Eric Dumazet Return-path: Received: from mail.avalus.com ([89.16.176.221]:35172 "EHLO mail.avalus.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755955Ab1EGSu4 (ORCPT ); Sat, 7 May 2011 14:50:56 -0400 In-Reply-To: <1304793749.3207.26.camel@edumazet-laptop> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: --On 7 May 2011 20:42:29 +0200 Eric Dumazet wrote: > Here is my trace here for one device deletion on one 8 core machine > > [ 800.447012] synchronize_rcu() in 15787 us > [ 800.455013] synchronize_rcu() in 7682 us > [ 800.464019] rcu_barrier() in 8487 us Would you mind trying it with my script to do veth devices? kill udev and do unshare -n first. I've done this on 2 different lots of hardware now, with 3 kernels 18 months apart. $ grep RCU .config # RCU Subsystem CONFIG_TREE_RCU=y # CONFIG_PREEMPT_RCU is not set # CONFIG_RCU_TRACE is not set CONFIG_RCU_FANOUT=64 # CONFIG_RCU_FANOUT_EXACT is not set CONFIG_RCU_FAST_NO_HZ=y # CONFIG_TREE_RCU_TRACE is not set # CONFIG_SPARSE_RCU_POINTER is not set # CONFIG_RCU_TORTURE_TEST is not set # CONFIG_RCU_CPU_STALL_DETECTOR is not set -- Alex Bligh