From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?ISO-8859-2?Q?Pawe=B3_Staszewski?= Subject: Re: [PATCH net-2.6] Re: rib_trie / Fix inflate_threshold_root. Now=15 size=11 bits Date: Sun, 05 Jul 2009 02:26:54 +0200 Message-ID: <4A4FF34E.7080001@itcare.pl> References: <20090630204141.GB3026@ami.dom.local> <4A4AA03D.5090808@itcare.pl> <20090701063651.GA4876@ff.dom.local> <20090701072409.GA12592@ff.dom.local> <4A4B2FA8.3040007@itcare.pl> <20090701101333.GB12715@ff.dom.local> <20090701110407.GC12715@ff.dom.local> <4A4BE06F.3090608@itcare.pl> <20090702053216.GA4954@ff.dom.local> <4A4C48FD.7040002@itcare.pl> <20090702060011.GB4954@ff.dom.local> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-2; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Linux Network Development list , Robert Olsson To: Jarek Poplawski Return-path: Received: from smtp.iq.pl ([86.111.241.19]:38060 "EHLO smtp.iq.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752465AbZGEA0y (ORCPT ); Sat, 4 Jul 2009 20:26:54 -0400 In-Reply-To: <20090702060011.GB4954@ff.dom.local> Sender: netdev-owner@vger.kernel.org List-ID: Jarek Poplawski pisze: > On Thu, Jul 02, 2009 at 07:43:25AM +0200, Pawe=B3 Staszewski wrote: > =20 >> Jarek Poplawski pisze: >> =20 >>> On Thu, Jul 02, 2009 at 12:17:19AM +0200, Pawe=B3 Staszewski wrote: >>> =20 >>> =20 >>>> Jarek Poplawski pisze: >>>> =20 >>>> =20 >>> ... >>> =20 >>> =20 >>>>> So, after your findings I'm about to recommend sending to -stable >>>>> 3 patches from net-2.6, with additional lowering of threshold_roo= t >>>>> settings, but it would be nice if you could give it a try with >>>>> CONFIG_PREEMPT instead of CONFIG_PREEMPT_NONE (if it doesn't brea= k >>>>> your other apps!) It is expected to work this time...;-) Maybe a >>>>> bit slower. >>>>> >>>>> =20 Ok kernel configured with CONFIG_PREEMPT and all this day work without any problems (with Jarek last patch). So in attached file trere is fib_tirestats I dont see any big change of (cpu load or faster/slower=20 routing/propagating routes from bgpd or something else) - in avg there=20 is from 2% to 3% more of CPU load i dont know why but it is - i change from "preempt" to "no preempt" 3 times and check this my "mpstat -P ALL= =20 1 30" always avg cpu load was from 2 to 3% more compared to "no preempt" Regards Pawe=B3 Staszewski =20 >>>>> =20 >>>>> =20 >>>> Patch applied to 2.6.29.5 with CONFIG_PREEMPT_NONE >>>> And working :) >>>> =20 >>>> =20 >>> Hmm... It should, because you tested very similar patch already;-) >>> Sorry if I didn't make it clear. >>> >>> =20 >>> =20 >> Yes i know there was almost identical one. >> And i see this was without sync rcu :) >> =20 > > Yes, it looks like we can't free memory so simple because of such hug= e > latencies. =20 > > =20 >>>> fib_triestats in attached file >>>> >>>> I think I can test it with PREEMPT enabled but first i must make s= ome=20 >>>> other tests of my apps that are on server. >>>> =20 >>>> =20 >>> It could probably matter only if you're using some broken out-of-tr= ee >>> patches. Otherwise the kernel is expected to work OK. >>> >>> =20 >>> =20 >> Im a little confused about using of PREEMPT kernel because of past >> there was many oopses / lockups :) but yes that was a little long ti= me ago. >> I will try to make this test today. >> >> =20 >>> Btw., it would be also interesting to check if there is any differe= nce >>> wrt. these route cache problems while PREEMPT is enabled. >>> =20 > > And you're very right! The place we're fixing is the best example. On > the other hand, I hope there is not many such places yet. But if we > test/fix it there will be one less... > > Jarek P. > > > =20