From owner-freebsd-net@FreeBSD.ORG Thu Jun 26 01:38:02 2008 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C497E1065676 for ; Thu, 26 Jun 2008 01:38:02 +0000 (UTC) (envelope-from erik@cepheid.org) Received: from mail.cepheid.org (aleph.cepheid.org [72.232.60.94]) by mx1.freebsd.org (Postfix) with ESMTP id A69868FC18 for ; Thu, 26 Jun 2008 01:38:02 +0000 (UTC) (envelope-from erik@cepheid.org) Received: by mail.cepheid.org (Postfix, from userid 1006) id B06AB9B4002; Wed, 25 Jun 2008 20:38:01 -0500 (CDT) Date: Wed, 25 Jun 2008 20:38:01 -0500 From: Erik Osterholm To: Max Laier Message-ID: <20080626013801.GA83308@aleph.cepheid.org> Mail-Followup-To: Erik Osterholm , Max Laier , freebsd-net@freebsd.org References: <20080624212639.GA41755@aleph.cepheid.org> <4c5bca29cfc1cdd3efa81ffb2f815675.squirrel@router> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4c5bca29cfc1cdd3efa81ffb2f815675.squirrel@router> User-Agent: Mutt/1.4.2.3i Cc: freebsd-net@freebsd.org Subject: Re: Why isn't ALTQ in GENERIC? X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 26 Jun 2008 01:38:02 -0000 On Wed, Jun 25, 2008 at 03:13:54AM +0200, Max Laier wrote: > Hi Erik, > > Am Di, 24.06.2008, 23:26, schrieb Erik Osterholm: > > Can anyone tell me if there are good reasons for explicitly leaving > > ALTQ out of the kernel? More specific to my circumstances, if I'm > > building kernels to be installed on every machine we deploy, is it > > worth building a separate kernel for ALTQ for those few boxes which > > will require it? > > > > Are there performance issues? Stability issues? Ultimately, I'm just > > surprised that it's not available in GENERIC if there isn't a good > > reason, but I can't find any documentation for that reason. > > Short answer: Historical reasons. > > Whole stroy: When ALTQ was added there were both performance and stability > concerns. For a long time we had a big #ifdef ALTQ in if_var.h to avoid > one additional check for if_queue enqueue opperations. These are now gone > and I personally don't see any issues that would prevent ALTQ from being > in GENERIC. However, it's unclear which disceplines to turn on by > default. I'd like to see ALTQ in GERNERIC, but I've been reluctant to > make the change on my own. If we can get a quorum here, I'll reconsider > it. Thanks for the explanation. I think that it would be nice to have in GENERIC, but my immediate concerns were for with the performance and stability. Thanks! Erik