From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755227AbaEFU10 (ORCPT ); Tue, 6 May 2014 16:27:26 -0400 Received: from relay3-d.mail.gandi.net ([217.70.183.195]:51008 "EHLO relay3-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751517AbaEFU1X (ORCPT ); Tue, 6 May 2014 16:27:23 -0400 Date: Tue, 6 May 2014 13:27:19 -0700 From: josh@joshtriplett.org To: Eric Dumazet Cc: Andi Kleen , David Miller , andi@firstfloor.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, tom.zanussi@linux.intel.com Subject: Re: [PATCH 08/24] net, diet: Make TCP metrics optional Message-ID: <20140506202719.GD21332@cloud> References: <1399328773-6531-9-git-send-email-andi@firstfloor.org> <20140505.231229.136734008603421707.davem@davemloft.net> <20140506032114.GP2382@two.firstfloor.org> <20140505.232327.578134514220748085.davem@davemloft.net> <20140506155703.GA20391@cloud> <1399394359.15399.20.camel@edumazet-glaptop2.roam.corp.google.com> <20140506183216.GM19657@tassilo.jf.intel.com> <1399407478.15399.81.camel@edumazet-glaptop2.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1399407478.15399.81.camel@edumazet-glaptop2.roam.corp.google.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 06, 2014 at 01:17:58PM -0700, Eric Dumazet wrote: > On Tue, 2014-05-06 at 11:32 -0700, Andi Kleen wrote: > > > We simply can not compete with user space, as a programmer is free to > > > keep what he really wants/needs. > > > > Not true. > > You can shake the kernel as much as you want, you wont make : > - a TCP socket > - a dentry > - an inode > - a file structure > - eventpoll structures (assuming epoll use) > - 2 dst per flow. > > In 1024 bytes of memory, and keep an efficient kernel to handle > arbitrary number of sockets using the venerable and slow BSD socket api. > > I was objecting to the "crazy things like LWIP" comment from Josh, not > to your patches in general. My primary statement was that it's crazy to use something like LWIP just because you want a *tiny* system. We could argue about using LWIP because you want a massively scalable system, or one that more closely couples userspace and the kernel, but that's not the current goal in any case. So let's drop that branch of the thread. :) > I actually took a look at them but stopped at patch 22 > > Adding ~1000 lines of code to save few KB was the point I gave up. Please consider ignoring that one and reading the rest; we could always handle the routing table issue separately. - Josh Triplett