From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752366AbaEFRD2 (ORCPT ); Tue, 6 May 2014 13:03:28 -0400 Received: from mail-pd0-f179.google.com ([209.85.192.179]:49174 "EHLO mail-pd0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751281AbaEFRD1 (ORCPT ); Tue, 6 May 2014 13:03:27 -0400 Message-ID: <1399395804.15399.27.camel@edumazet-glaptop2.roam.corp.google.com> Subject: Re: [PATCH 08/24] net, diet: Make TCP metrics optional From: Eric Dumazet To: josh@joshtriplett.org Cc: David Miller , andi@firstfloor.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, tom.zanussi@linux.intel.com, ak@linux.intel.com Date: Tue, 06 May 2014 10:03:24 -0700 In-Reply-To: <20140506164546.GB20536@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> <20140506164546.GB20536@cloud> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2014-05-06 at 09:45 -0700, josh@joshtriplett.org wrote: > Sounds like we have some optimization to do, then; there's no > fundamental unfixable reason for that delta. I think you have little idea of the reasons for this delta. Some servers handle 10 millions of TCP flows, using as little as 1KB per connection in user space, all included. Do you have an idea of how much memory is needed for 10 millions TCP sockets in the kernel ?