From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?ISO-8859-1?Q?Ra=FAl_Hern=E1ndez?= Subject: Re: QoS hot changes changes (tc) Date: Tue, 30 Jun 2009 08:21:34 +0200 Message-ID: <3f847c820906292321w1b85a423o2f5b25badddb9dd2@mail.gmail.com> References: <3f847c820906260619g238b6a17ub17af3f27da83ef5@mail.gmail.com> <4A469242.4070000@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "netdev@vger.kernel.org >> Linux Netdev List" To: Jarek Poplawski Return-path: Received: from fg-out-1718.google.com ([72.14.220.152]:5266 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752778AbZF3GVb convert rfc822-to-8bit (ORCPT ); Tue, 30 Jun 2009 02:21:31 -0400 Received: by fg-out-1718.google.com with SMTP id e21so1041025fga.17 for ; Mon, 29 Jun 2009 23:21:34 -0700 (PDT) In-Reply-To: <4A469242.4070000@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: Thanks Jarek ! I will try to test them running traffic to see how they are doing. I miss some documentation related to these stuff :-(. Regards, Raul 2009/6/27 Jarek Poplawski : > Ra=FAl Hern=E1ndez wrote, On 06/26/2009 03:19 PM: > >> Hi there, >> >> I am trying to characterize the situation in which we perform a chan= ge >> in the shaping done by the Linux kernel (tc+qdisc), specifically whe= n >> modifying the bandwidth as a hot change while shaping with a previou= s >> bw value. The system I am describing performs shaping per stream >> (uplink and/or dowinlink or total), just marking the TOS of the ip >> packet and provisioning the kernel via 'tc' to shape the packets. >> >> My question is whether someone has tried to modify bw parameters, ie= : >> move from 90 to 45 kb/s while the queues are already being populated >> with trafffic .Do not know if the shaper algorithm is able to adjust >> the bw without service disruption/experiment transitory behavior as = I >> guess the algorithm must have some kind of feedback which depends of >> the bytes already shaped and the value of the bw itself (ie: leaky >> bucket). >> >> Any experience with this kind of changes :-) ? Thx ! > > No experience in measuring the effects of such changes, but looking > into code shows it depends on a shaper algorithm: tbf seems to reset > the queue, htb doesn't. > > Jarek P. > --=20 "We cannot change the cards we are dealt, just how we play the hand.