From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail2.tohojo.dk (mail2.tohojo.dk [77.235.48.147]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by huchra.bufferbloat.net (Postfix) with ESMTPS id 4711221F420 for ; Tue, 3 Nov 2015 04:59:47 -0800 (PST) X-Virus-Scanned: amavisd-new at mail2.tohojo.dk DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=toke.dk; s=201310; t=1446555584; bh=bKrxIf+4iVp4khGCHiehe29lUiZ0S+Ft+KQQIugMMes=; h=From:To:Subject:Date; b=LZUuZC2lBnSVwgyNjyH13pGYhDd2iQtOErlnoVkb/mDB0/1Dvg3OFSnD7d4/yRogT D5QUSHR0ZHZ0+2WgjP21VOQ3nzDDLozlR8SG0f82U2tYsNS9fRVfvrwemM2EYgxXsy wbDI/KKLBLddq385xjvYiCjjmAqQLfkdPXZdHeRg= Received: by alrua-kau.kau.toke.dk (Postfix, from userid 1000) id 135CEC402A1; Tue, 3 Nov 2015 13:59:44 +0100 (CET) From: =?utf-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= To: cake@lists.bufferbloat.net Date: Tue, 03 Nov 2015 13:59:44 +0100 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <87oafbnsqn.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain Subject: [Cake] Correct 'change' behaviour X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 Nov 2015 13:00:35 -0000 So we've seen a couple of issues with reconfiguration being weird (i.e. retaining previous values). Looking at the code in cake_change() and the iproute2 code, this seems to stem from the fact that tc only sets the parameters (in the netlink message) that are actually specified on the command line, and the kernel only changes the parameters specified in the netlink message. This leads to the different behaviour: On init, not specifying a parameter means "give me a sensible default", whereas on a reconfigure it means "don't change this parameter from its current value". This is obviously inconsistent. I'd argue that the right thing to do is the former in all cases; is there any reason why that would not be the case? If not, I'll go fix it :) -Toke