From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] bonding: add some slack to arp monitoring time limits Date: Fri, 31 Aug 2012 16:37:43 -0400 (EDT) Message-ID: <20120831.163743.1055530014542819729.davem@davemloft.net> References: <50351CC5.3030109@genband.com> <24655.1345660922@death.nxdomain> <20120830220247.GB17263@midget.suse.cz> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: fubar@us.ibm.com, chris.friesen@genband.com, andy@greyhouse.net, netdev@vger.kernel.org, ptesarik@suse.cz To: jbohac@suse.cz Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:53440 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754936Ab2HaUhr (ORCPT ); Fri, 31 Aug 2012 16:37:47 -0400 In-Reply-To: <20120830220247.GB17263@midget.suse.cz> Sender: netdev-owner@vger.kernel.org List-ID: From: Jiri Bohac Date: Fri, 31 Aug 2012 00:02:47 +0200 > Currently, all the time limits in the bonding ARP monitor are in > multiples of arp_interval -- the time interval at which the ARP > monitor is periodically scheduled. > > With a fast network round-trip and a little scheduling latency > of the ARP monitor work, a limit of n*delta_in_ticks may > effectively mean (n-1)*delta_in_ticks. > > This is fatal in case of n==1 (the link will stay down > forever) and makes the behaviour non-deterministic in all the > other cases. > > Add a delta_in_ticks/2 time slack to all the time limits. > > Signed-off-by: Jiri Bohac Applied to net-next, thanks.