From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net (mout.gmx.net [212.227.17.21]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mout.gmx.net", Issuer "TeleSec ServerPass DE-1" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id BDEAE21F4E7 for ; Tue, 3 Nov 2015 00:34:36 -0800 (PST) Received: from u-089-d061.biologie.uni-tuebingen.de ([134.2.89.61]) by mail.gmx.com (mrgmx103) with ESMTPSA (Nemesis) id 0LpbfG-1aQ6dd0puw-00fQf5; Tue, 03 Nov 2015 09:34:31 +0100 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) From: Sebastian Moeller In-Reply-To: Date: Tue, 3 Nov 2015 09:34:29 +0100 Content-Transfer-Encoding: quoted-printable Message-Id: References: <87pozspckj.fsf@toke.dk> <6A2609D9-7747-487B-9484-ECC69C50DE96@gmx.de> To: Jonathan Morton X-Mailer: Apple Mail (2.1878.6) X-Provags-ID: V03:K0:/Toctha5u9T2WZXuVRatsOAgJ6onSGDk+3OpcsMR33Gfo7Wrc84 bVh7MUaErFXbRnWnHKvzelfvRDq4ICgQVl6oTQV07Q2k9plQZC396rROutKP2+6NlDIWo0y pIJ1POQ5mjgSjjaLV0aAUjh/R3sFuSIO2ddrG59C4gVIv2klENUEplgY8C46zcIFtEKmM4z zg4R0O/8BbK4NZYMiLppg== X-UI-Out-Filterresults: notjunk:1;V01:K0:dbZJ4LDrAFk=:JCZZ+8YspdNzWwKnn9TxZp w8QI/t3XFEoGIQF7lHGWhTchoCnJ1ePo8ziBhEks76G5D2XiOYAS+6g6WrewodHewiGw+Xjio zioo5EnuBiBAmbfagTSMqqmmu1J6+oGVkABj7oJeWQ1uMkCsopTj12PH04xDdNNxJRs3Rj4Hg igDAznSDlLdllyhIgT+7OPHZVzwLhKdQ3Z/CP95ZJo88u/0VMFGPjXBX3PSkRHjlbdjHT+ZB+ CPHPRShXB1206gbqtUKBidLS39SKHekq2bvzbFEb9Lg/6qBTiYj4JrUc14iT6pkaSCLif9Zlw FJtTfcTxTtho4G+kpkGPgKXyebg9csHrGxCPZ7o0iKYPR9HZIhuvTzLy/L0KZHc3AFiLPb4he hw/89/aYHD6ZmOKjK86ejoqWvT204vKuMVzZSScvt4wADS36JFLMxUmHMf4Kej9ib21Uyndyo tQ3Jsip0Cg5jXKN2EWNw7hyFERhfUJUBeTufV7qwQZjM7mgnqkWh5dczZuOwc6dEItnlrgOY6 Cpm5mcp2okzRNMCjNDwVKsA3nO3uJaBi6Iak1pWfQHGpJn4v5ZRqPfTKoTA0Tt2LP8hnLyznz c/07enaTtIxGn29/XZzszXQbCrn21c0/xFHxKHhpbu4lTgwUKhaL32kwbX53LpCpRCTA53LLQ L3sAUoHwJ+LvmKusN3tFi3BqE60wXH8SXy7zWhqCPDbW7leSUtYBLrniLS3th2SLsb3yEBKgq E1gquRCINq3g6BUoF0NszyCgUHB01r4bm6tUtOhCuV+JpCPwDU1/2WTgTDq4ZXEkJEMoAwkFD xXxywmO Cc: cake@lists.bufferbloat.net Subject: Re: [Cake] Long-RTT broken again 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 08:34:59 -0000 Hi Jonathan, On Nov 3, 2015, at 09:25 , Jonathan Morton = wrote: >=20 >> On 3 Nov, 2015, at 10:20, Sebastian Moeller wrote: >>=20 >> Also what about the BUG_ON I managed to trigger during my testing? >=20 > That turned out to be a flawed condition, which I=92ve already fixed. Excellent, thanks a lot. I would not have repeatedly brought = this up, if I had known it fixed, Call me weird, but I am not too keen = to look at the source to see whether =93reported=94 issues are fixed. I = also note it still is a BUG_ON ()actually there are two in sch_cake) and = that still has the issue whether cake is important enough to hose a = computer on failure=85 My understanding from luring on LKML is that = under-justified BUG_ONs are frowned upon=85 Why is that an issue? In my = case I needed physical access to reboot the machine, which for remote = servers gets difficult... > It=92s necessary for something like that to be there, because there = is a fixed, static allocation of tins; exceeding that number would = result in a buffer overflow. The only way to do so is to add a new = Diffserv scheme with more than eight tins, which isn=92t outside the = bounds of possibility in the future, though unlikely in the short term. Sure, but BUG_ON is the big gun that will most likely make the = machine unusable (at least it wedged my opensuse 13.2 machine hard = enough that a reboot was required); which I believe is too drastic for a = failed qdisc, but I could be wrong=85 Best Regards Sebastian >=20 > - Jonathan Morton >=20