Cake is expected to handle traffic in 2 steps : First is on the basis of host Second is within every host, on the basis of flow So, if I limit traffic to 20Mbps shared across 2 host A & B, Following are various scenarios, expectation and observations 1. If either A or B is downloading, they will be getting speed of 20Mbps Observation: Meeting with expectation 2. If both A & B downloads (single download each), each will be getting speed of 20Mbps Observation: Meeting with expecation but its very jittery (around 20%), i.e. speed varies from 8Mbps to 12 Mbps. If I use fq_codel speed is same BUT jitter is very less (around 1%). 3. Now if A starts 3 downloads, and B is still having single download, A each download should be around 3.3 Mbps and B should be around 10Mbps Observation: Around 5 Mbps for each download with lot of jitter, i.e. no advantage of having CAKE!!! Linux Kernel 4.20 For case 3, output of command : tc -s class show dev eno2 class htb 1:1 root leaf 8003: prio 1 rate 20000Kbit ceil 20000Kbit burst 200Kb cburst 1600b Sent 688474645 bytes 455058 pkt (dropped 0, overlimits 381196 requeues 0) rate 19874Kbit 1641pps backlog 21196b 14p requeues 0 lended: 382532 borrowed: 0 giants: 0 tokens: 1260573 ctokens: -9427 class cake 8003:44f parent 8003: (dropped 3404, overlimits 0 requeues 0) backlog 9084b 6p requeues 0 class cake 8003:516 parent 8003: (dropped 3565, overlimits 0 requeues 0) backlog 0b 0p requeues 0 class cake 8003:590 parent 8003: (dropped 3023, overlimits 0 requeues 0) backlog 4542b 3p requeues 0 class cake 8003:605 parent 8003: (dropped 1772, overlimits 0 requeues 0) backlog 7570b 5p requeues 0
