From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.toke.dk (mail.toke.dk [45.145.95.4]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 3ED283CB37; Tue, 18 Feb 2020 13:35:33 -0500 (EST) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=toke.dk; s=20161023; t=1582050931; bh=0MzJSAL/EMLidYVlANRYb2fv7e9ASNIvyam9+LNc4fg=; h=From:To:Subject:In-Reply-To:References:Date:From; b=LHWNb1iRfPzJWQxFN7IY/3El1hPMtwGNGwccNlitwRuhna/HcV5x5z9hxlTcP7zIc WKPrjrK1fi/Yw6Dzvbw82jZg5z+88lAuDQKWQDVGQgOjUe8fCTXmokPy7rFHHqDNBv +zf9OMFvS6E7hEZ1MecUC6wdjmrGTsLRjE9gNJEN5SoAG5GlcwP8kVlUjOZnJEk3LN FiWpZ6MF17NnEt4K0u6mv+2uZ3ymXr6MgfZUa3W3Ir8ZmTqmnDf4LwJiteeZSY9R1F IecxY/5zACqVWNp9t6Fc0zUvR+A6CeIjGyGeZOm7KaCylCMUrvNpH/1QcS85CJmOvU /dxyDvrKcloNQ== To: Rich Brown , bloat@lists.bufferbloat.net, cerowrt-devel-request@lists.bufferbloat.net In-Reply-To: References: Date: Tue, 18 Feb 2020 19:35:31 +0100 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <87h7znyc98.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Bloat] Debugging a crash X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 Feb 2020 18:35:33 -0000 Rich Brown writes: > Folks, > > I was running OpenWrt 19.07-rc2 on my Archer C7v2, and experienced a > potentially-repeatable crash under heavy network traffic load. > > I was uploading several long videos to Youtube (> 5GBytes each) and > watching Netflix on my 7mbps/768kbps DSL connection. Things were > working fine (latency remained acceptable - YAY SQM!) My upstream pipe > (slow as it is) was totally filled by the three competing uploads, and > Netflix was doing its best to show me the West Wing. > > A couple times during the evening, the Netflix stream just crapped out > and I lost the connection. (Infinite buffering message on-screen, > couldn't get to Google, etc. The LuCI GUI showed uptime of a minute or > so, and then things were fine again.) > > I now have OpenWrt 19.07.1 installed, and have a little bandwidth for > repeating the experiment. > > What debugging information should I turn on/look for in case this > happens again? Thanks. If the box reboots, this sounds like a kernel oops. In which case, we'd really need a kernel stack dump to debug it. Which I'm not sure there's a good way to get on OpenWrt without attaching a serial console :( Unless of course you can find a reliable way to reproduce it without too much delay, in which case someone with a serial console can take a look, I guess :) -Toke