From mboxrd@z Thu Jan 1 00:00:00 1970 From: starlight@binnacle.cx Subject: Re: big picture UDP/IP performance question re 2.6.18 -> 2.6.32 Date: Wed, 05 Oct 2011 11:12:15 -0400 Message-ID: <6.2.5.6.2.20111005110324.03a9df10@binnacle.cx> References: <6.2.5.6.2.20111003112108.03a83a28@binnacle.cx> <1317820942.6766.26.camel@twins> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: Eric Dumazet , linux-kernel@vger.kernel.org, netdev , Willy Tarreau , Ingo Molnar To: Peter Zijlstra , Christoph Lameter Return-path: In-Reply-To: <1317820942.6766.26.camel@twins> References: <6.2.5.6.2.20111003112108.03a83a28@binnacle.cx> <1317820942.6766.26.camel@twins> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org At 03:22 PM 10/5/2011 +0200, Peter Zijlstra wrote: >On Tue, 2011-10-04 at 14:16 -0500, Christoph Lameter wrote: >I suppose all this testing and feedback we receive >from you really helps us keep the performance >levels you want.. Oh wait, that's 0. Well I have to admit that I've looked into the future (i.e. tested kernel.org releases) only on occasion. To the extent that performance wasn't looking great I harbored an apparently over optimistic hope that things would get tuned/fixed in the process somewhere. In particular I was thinking that RH might do something impressive with RHEL 6 where Novell failed with SLES 11. However, if anything the downstream is fiddling less and less with the kernel as it becomes ever more complex. >Clearly none of the tests being ran on a regular >basis, by for instance the Intel regression team, >covers your needs. Start by fixing that. I could create a test case. It's quite a lot more than trivial, but not ridiculous either. That UDP is broken on everything past 2.6.27 may goad me into the effort. Have had a fairly excellent experience WRT the hugepage kernel corruption bugs I reported 18 months or so ago. Not only did the kernel developers fix them, the fixes made it downstream into RHEL fairly quickly. So that does encourage me.