From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from uplift.swm.pp.se (ipv6.swm.pp.se [IPv6:2a00:801::f]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 9A21B3B29E for ; Wed, 31 Jul 2019 03:58:04 -0400 (EDT) Received: by uplift.swm.pp.se (Postfix, from userid 501) id 2803BB2; Wed, 31 Jul 2019 09:58:03 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=swm.pp.se; s=mail; t=1564559883; bh=x0SIdJv1gKrjCw5ZaC/4EeVpwlUV7joaWWVIzlTGntE=; h=Date:From:To:Subject:From; b=oY5kFy6W0PpCYgkVLM6dhNUU27w41wMjB11TG7xGpe8pmHTSTWRqWECEmO0Asw5VP 34yzdQLkrQQN1wAJhHGxWZfFEnaVQfK56/in0gLNz8xPNyxmFbNJa2q8OR0Dbli98G uloLbD8VDSB4CbFpdjy5Cbhf9RhwXp0CtWSkV7/k= Received: from localhost (localhost [127.0.0.1]) by uplift.swm.pp.se (Postfix) with ESMTP id 25797AF for ; Wed, 31 Jul 2019 09:58:03 +0200 (CEST) Date: Wed, 31 Jul 2019 09:58:03 +0200 (CEST) From: Mikael Abrahamsson To: bloat@lists.bufferbloat.net Message-ID: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) Organization: People's Front Against WWW MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset=US-ASCII Subject: [Bloat] weird problem WRT1200 + CAKE on OpenWrt 18.06.2 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: Wed, 31 Jul 2019 07:58:04 -0000 Hi, I've been running openwrt 18.06.2 for a long time on my WRT1200AC, with CAKE, and everything has been great. I always got A+ in dslreports for bufferbloat. I have a 250/100 ETTH connection (IP over ethernet native, no PPPoE, no PON). I noticed some intermittent network stuttering issues I wanted to diagnose last week, so I started looking into this. When doing the test I get +100ms spikes in the downstream direction when I run CAKE. If I instead switch to FQ_CODEL I do not see these spikes. As a matter of fact, if I set my downstream to 300 when running cake and let my ISP handle the buffering then I get an average of 5-10ms worth of buffering with no spikes. My ISP isn't bloated in that direction. # tc qdisc show dev eth1.2 qdisc cake 801f: root refcnt 2 bandwidth 100Mbit diffserv3 triple-isolate nonat nowash no-ack-filter split-gso rtt 100.0ms noatm overhead 22 qdisc ingress ffff: parent ffff:fff1 ---------------- tc qdisc show dev ifb4eth1.2 qdisc cake 8020: root refcnt 2 bandwidth 240Mbit diffserv3 triple-isolate nonat nowash no-ack-filter split-gso rtt 100.0ms noatm overhead 22 http://www.dslreports.com/speedtest/52542158 is the result I get with above settings. http://www.dslreports.com/speedtest/52542263 is the result with FQ_CODEL: # tc qdisc show dev eth1.2 qdisc htb 1: root refcnt 2 r2q 10 default 18 direct_packets_stat 0 direct_qlen 1000 qdisc fq_codel 120: parent 1:12 limit 1001p flows 1024 quantum 300 target 5.0ms interval 100.0ms memory_limit 4Mb ecn qdisc fq_codel 130: parent 1:13 limit 1001p flows 1024 quantum 300 target 5.0ms interval 100.0ms memory_limit 4Mb ecn qdisc fq_codel 110: parent 1:11 limit 1001p flows 1024 quantum 300 target 5.0ms interval 100.0ms memory_limit 4Mb ecn qdisc ingress ffff: parent ffff:fff1 ---------------- # tc qdisc show dev ifb4eth1.2 qdisc htb 1: root refcnt 2 r2q 10 default 18 direct_packets_stat 0 direct_qlen 32 qdisc fq_codel 120: parent 1:12 limit 1001p flows 1024 quantum 1500 target 5.0ms interval 100.0ms memory_limit 4Mb ecn qdisc fq_codel 130: parent 1:13 limit 1001p flows 1024 quantum 300 target 5.0ms interval 100.0ms memory_limit 4Mb ecn qdisc fq_codel 110: parent 1:11 limit 1001p flows 1024 quantum 500 target 5.0ms interval 100.0ms memory_limit 4Mb ecn How do I diagnose this further? -- Mikael Abrahamsson email: swmike@swm.pp.se