From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v2 net-next] neigh: reduce arp latency Date: Fri, 12 Aug 2011 02:57:08 -0700 (PDT) Message-ID: <20110812.025708.1569052368114569085.davem@davemloft.net> References: <1312904434.2371.39.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> <1312913758.2547.8.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: ja@ssi.bg, netdev@vger.kernel.org To: eric.dumazet@gmail.com Return-path: Received: from shards.monkeyblade.net ([198.137.202.13]:52077 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752537Ab1HLJ5S convert rfc822-to-8bit (ORCPT ); Fri, 12 Aug 2011 05:57:18 -0400 In-Reply-To: <1312913758.2547.8.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: =46rom: Eric Dumazet Date: Tue, 09 Aug 2011 20:15:58 +0200 > Le mardi 09 ao=FBt 2011 =E0 20:06 +0300, Julian Anastasov a =E9crit : >=20 >> To be correct with old NUD_INCOMPLETE logic may be we can use=20 >> max(neigh->parms->retrans_time, HZ/2) here instead of HZ? >>=20 >=20 > Thanks Julian a lot for reviewing, here is v2 adressing this point. >=20 > [PATCH v2 net-next] neigh: reduce arp latency >=20 > Remove the artificial HZ latency on arp resolution. >=20 > Instead of firing a timer in one jiffy (up to 10 ms if HZ=3D100), let= s > send the ARP message immediately. >=20 > Before patch : >=20 > # arp -d 192.168.20.108 ; ping -c 3 192.168.20.108 > PING 192.168.20.108 (192.168.20.108) 56(84) bytes of data. > 64 bytes from 192.168.20.108: icmp_seq=3D1 ttl=3D64 time=3D9.91 ms > 64 bytes from 192.168.20.108: icmp_seq=3D2 ttl=3D64 time=3D0.065 ms > 64 bytes from 192.168.20.108: icmp_seq=3D3 ttl=3D64 time=3D0.061 ms >=20 > After patch : >=20 > $ arp -d 192.168.20.108 ; ping -c 3 192.168.20.108 > PING 192.168.20.108 (192.168.20.108) 56(84) bytes of data. > 64 bytes from 192.168.20.108: icmp_seq=3D1 ttl=3D64 time=3D0.152 ms > 64 bytes from 192.168.20.108: icmp_seq=3D2 ttl=3D64 time=3D0.064 ms > 64 bytes from 192.168.20.108: icmp_seq=3D3 ttl=3D64 time=3D0.074 ms >=20 > Signed-off-by: Eric Dumazet Applied.