From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by huchra.bufferbloat.net (Postfix) with ESMTP id 9AA9A202102 for ; Tue, 4 Jun 2013 13:21:59 -0700 (PDT) Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r54KLnhE005575 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 4 Jun 2013 16:21:49 -0400 Received: from localhost (ovpn-116-42.ams2.redhat.com [10.36.116.42]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r54KLclN023160; Tue, 4 Jun 2013 16:21:38 -0400 Date: Tue, 4 Jun 2013 22:21:35 +0200 From: Jesper Dangaard Brouer To: Eric Dumazet , netdev@vger.kernel.org Message-ID: <20130604222135.67eedab8@redhat.com> In-Reply-To: <1370365908.24311.222.camel@edumazet-glaptop> References: <20130529151330.22c5c89e@redhat.com> <20130604141342.00c8eb9f@redhat.com> <1370359133.24311.208.camel@edumazet-glaptop> <1370361306.24311.214.camel@edumazet-glaptop> <1370361727.24311.215.camel@edumazet-glaptop> <1370365908.24311.222.camel@edumazet-glaptop> Organization: Red Hat Inc. Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 Cc: Toke =?UTF-8?B?SMO4aWxhbmQtSsO4cmdlbnNlbg==?= , Mike Frysinger , Jiri Pirko , bloat@lists.bufferbloat.net, Jiri Benc , Patrick McHardy , Steven Barth , David Miller , Jussi Kivilinna , Felix Fietkau , Michal Soltys Subject: Re: [Bloat] [PATCH] net_sched: htb: do not mix 1ns and 64ns time units X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Jun 2013 20:21:59 -0000 On Tue, 04 Jun 2013 10:11:48 -0700 Eric Dumazet wrote: > From: Eric Dumazet >=20 > commit 56b765b79 ("htb: improved accuracy at high rates") added > another regression for low rates, because it mixes 1ns and 64ns time > units. >=20 > So the maximum delay (mbuffer) was not 60 second, but 937 ms. >=20 > Lets convert all time fields to 1ns as 64bit arches are becoming the > norm. I'm of-cause happy as I need this fixed for big-HW machines at Red Hat. But how is this 64-bit usage going to affect performance for smaller ARM/MIPS based home routers, where shaping at these low rates is more relevant? (I'm just asking because I don't know, and just test this on a 24-CPU machine). Tested-by: Jesper Dangaard Brouer I have tested you patch, and it works for me. Tested shaping at 100Kbit/s: - max "rate 100656bit" on dev lo - max "rate 102016bit" on a real 1 Gbit/s NIC (dev eth63). - max "rate 103256bit" on a real 10 Gbit/s NIC (dev eth31). The traffic "of-cause" spikes due to the GSO frames, if measuring the traffic at a higher resolution (I've seen upto 3 sec without traffic). Thanks for the quick fix! :-))) --=20 Best regards, Jesper Dangaard Brouer MSc.CS, Sr. Network Kernel Developer at Red Hat Author of http://www.iptv-analyzer.org LinkedIn: http://www.linkedin.com/in/brouer Reproducer commands: tc qdisc add dev lo root handle 1: htb default 1 tc class add dev lo parent 1: classid 1:1 htb rate 100kbit netserver netperf -t TCP_STREAM -l 60 -H 127.0.0.1 -- -m 1024 Measuring the qdisc "rate" via: tc -s -d class show dev lo classid 1:1 Data: =3D=3D=3D=3D=3D =46rom dev "lo": -------------- class htb 1:1 root prio 0 quantum 1250 rate 100000bit ceil 100000bit burst = 1600b/1 mpu 0b overhead 0b cburst 1600b/1 mpu 0b overhead 0b level 0=20 Sent 597719 bytes 64 pkt (dropped 942, overlimits 0 requeues 0)=20 rate 100656bit 1pps backlog 0b 1p requeues 0=20 lended: 64 borrowed: 0 giants: 0 tokens: -27387576 ctokens: -27387576 =46rom 1Gbit/s dev eth63: ----------------------- class htb 1:1 root prio 0 quantum 1250 rate 100000bit ceil 100000bit burst = 1600b/1 mpu 0b overhead 0b cburst 1600b/1 mpu 0b overhead 0b level 0=20 Sent 1801152 bytes 3224 pkt (dropped 0, overlimits 0 requeues 0)=20 rate 102016bit 9pps backlog 0b 12p requeues 0=20 lended: 2284 borrowed: 0 giants: 0 tokens: -18923820 ctokens: -18923820 =46rom 10Gbit/s dev eth31: ------------------------ class htb 1:1 root prio 0 quantum 1250 rate 100000bit ceil 100000bit burst = 1600b/1 mpu 0b overhead 0b cburst 1600b/1 mpu 0b overhead 0b level 0=20 Sent 855814 bytes 581 pkt (dropped 0, overlimits 0 requeues 0)=20 rate 103256bit 9pps backlog 0b 9p requeues 0=20 lended: 81 borrowed: 0 giants: 0 tokens: -45419150 ctokens: -45419150