From mboxrd@z Thu Jan 1 00:00:00 1970 From: Denys Fedoryshchenko Subject: Re: HTB going crazy over ~5Gbit/s (4.12.9, but problem present in older kernels as well) Date: Wed, 13 Sep 2017 20:35:41 +0300 Message-ID: <5a95e6550a304545fbde95360985c018@nuclearcat.com> References: <4cd23914d8cc2cf5caf78cb5654fb245@nuclearcat.com> <1505319370.15310.169.camel@edumazet-glaptop3.roam.corp.google.com> <9b8cdc2b39fdd2d0be7b5f559b2034e7@nuclearcat.com> <1505320949.15310.173.camel@edumazet-glaptop3.roam.corp.google.com> <1505321747.15310.175.camel@edumazet-glaptop3.roam.corp.google.com> <57baf3c3ea2544ed4d53967b7a2d0e36@nuclearcat.com> <1505323222.15310.177.camel@edumazet-glaptop3.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Cc: Linux Kernel Network Developers , netdev-owner@vger.kernel.org To: Eric Dumazet Return-path: Received: from nuclearcat.com ([144.76.183.226]:56346 "EHLO nuclearcat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751092AbdIMRfo (ORCPT ); Wed, 13 Sep 2017 13:35:44 -0400 In-Reply-To: <1505323222.15310.177.camel@edumazet-glaptop3.roam.corp.google.com> Sender: netdev-owner@vger.kernel.org List-ID: On 2017-09-13 20:20, Eric Dumazet wrote: > On Wed, 2017-09-13 at 20:12 +0300, Denys Fedoryshchenko wrote: > >> For my case, as load increased now, i am hitting same issue (i tried >> to >> play with quantum / bursts as well, didnt helped): >> >> tc -s -d class show dev eth3.777 classid 1:111;sleep 5;tc -s -d class >> show dev eth3.777 classid 1:111 >> class htb 1:111 parent 1:1 leaf 111: prio 0 quantum 50000 rate 20Gbit >> ceil 100Gbit linklayer ethernet burst 100000b/1 mpu 0b cburst >> 100000b/1 >> mpu 0b level 0 >> Sent 864151559 bytes 730566 pkt (dropped 15111, overlimits 0 >> requeues >> 0) >> backlog 73968000b 39934p requeues 0 >> lended: 499867 borrowed: 0 giants: 0 >> tokens: 608 ctokens: 121 >> > > You have drops (and ~40,000 packets in backlog) > > >> class htb 1:111 parent 1:1 leaf 111: prio 0 quantum 50000 rate 20Gbit >> ceil 100Gbit linklayer ethernet burst 100000b/1 mpu 0b cburst >> 100000b/1 >> mpu 0b level 0 >> Sent 1469352160 bytes 1243649 pkt (dropped 42933, overlimits 0 >> requeues >> 0) >> backlog 82536047b 39963p requeues 0 >> lended: 810475 borrowed: 0 giants: 0 >> tokens: 612 ctokens: 122 >> >> (1469352160-864151559)/5*8 >> 968320961.60000000000000000000 >> Less than 1Gbit and it's being throttled > > It is not : "overlimits 0" means this class was not throttled. Overlimits never appear in HTB as i know, here is simulation on this class that have constant "at least" 1G traffic, i throttled it to 1Kbit to simulate forced drops: shapernew ~ # sh /etc/shaper.cfg;sleep 1;tc -s -d class show dev eth3.777 classid 1:111;tc qdisc del dev eth3.777 root class htb 1:111 parent 1:1 leaf 111: prio 0 quantum 50000 rate 1Kbit ceil 1Kbit linklayer ethernet burst 31280b/1 mpu 0b cburst 31280b/1 mpu 0b level 0 Sent 134350019 bytes 117520 pkt (dropped 7819, overlimits 0 requeues 0) backlog 7902126b 4976p requeues 0 lended: 86694 borrowed: 0 giants: 0 tokens: -937500000 ctokens: -937500000