From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755437Ab0I3Mcs (ORCPT ); Thu, 30 Sep 2010 08:32:48 -0400 Received: from smtp.df.ru ([195.42.160.16]:48106 "EHLO smtp.df.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753429Ab0I3Mcq (ORCPT ); Thu, 30 Sep 2010 08:32:46 -0400 Date: Thu, 30 Sep 2010 16:30:48 +0400 From: Alexey Vlasov To: Eric Dumazet Cc: Linux Kernel Mailing List , netdev Subject: Re: Packet time delays on multi-core systems Message-ID: <20100930123048.GA4094@beaver.vrungel.ru> References: <20100929191851.GC86786@beaver.vrungel.ru> <1285796721.5211.156.camel@edumazet-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline In-Reply-To: <1285796721.5211.156.camel@edumazet-laptop> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 29, 2010 at 11:45:21PM +0200, Eric Dumazet wrote: > But if you send SYN packets in the same time, (logged), this might > slow > down the reception (and answers) of ICMP frames. LOG target can be > quite > expensive... Yes, it's clear that some slow down can appear, but 100 ms is too much, and this happens at 200 SYN packets in 2 minutes just as in my example. On old servers where some tx/rx are missing in NIC card I don't see such a situation even at more then 1000 SYN-packets per sec. > Is using other rules gives same problem ? > > iptables -A OUTPUT -p tcp -m tcp --dport 80 --tcp-flags No, only LOG gives such a scheme. -- BRGDS. Alexey Vlasov.