TC HTB r2q

HTB:
Quantum of Class 10001 is big. Consider r2q change.

According to HTB's official documentation, Quantum is able to "borrow" at a time, and say that the value is best as small as possible, but greater than the MTU, and that this value is not manually set, it is calculated based on the value of r2q.


Changing burst would not remove the warning. R2q is ' rate to quantum ' is used

To calculate the quantum for each class:quantum = rate/r2q. Quantum must

Be < quantum < 60000. Otherwise you'll get warnings from the kernel.

Solution:choose r2q so for each class< Quantum < 60000

Or Choose the best r2q you can and specify the quantum manually if you add a

Class.



> TC Qdisc Add dev eth0 root handle 1:HTB default 10

Default r2q = 10.



> TC class Add dev eth0 parent 1:classid 1:1 HTB rate 100mbit burst 2k

> TC class Add dev eth0 parent 1:1 classid 1:10 HTB rate 80mbit ceil 100mbit

> Burst 2k

>

> TC class Add dev eth0 parent 1:1 classid 1:11 HTB rate 128kbit burst 2k

> TC class Add dev eth0 parent 1:11 classid 1:21 HTB rate 16kbit ceil 56kbit

> Burst 2k

> TC class Add dev eth0 parent 1:11 classid 1:22 HTB rate 16kbit ceil 40kbit

> Burst 2k

> TC class Add dev eth0 parent 1:11 classid 1:23 HTB rate 16kbit ceil 72kbit

> Burst 2k

> TC class Add dev eth0 parent 1:11 classid 1:24 HTB rate 16kbit ceil 64kbit

> Burst 2k

> TC class Add dev eth0 parent 1:11 classid 1:25 HTB rate 16kbit ceil 40kbit

> Burst 2k

> TC class Add dev eth0 parent 1:11 classid 1:26 HTB rate 16kbit ceil 40kbit

> Burst 2k

> TC class Add dev eth0 parent 1:11 classid 1:27 HTB rate 16kbit ceil 32kbit

> Burst 2k

> TC class Add dev eth0 parent 1:11 classid 1:28 HTB rate 16kbit ceil 56kbit

> Burst 2k

Smallest rate:16kbit = 2 kilobyt/r2q (=10) = 200.  And this is < 1500. So

You get warnings.

Biggest Rate:100mbit = 12.5 mbyte/r2q = 1.2 MByte > 60.000. So get

Warnings.



If you do

TC Qdisc Add dev eth0 root handle 1:htb default ten r2q 1

Smallest rate:16kbit = 2kilobyte/r2k = 2000.  And this is > 1500. So no

Warnings.

Biggest Rate:100mbit = 12.5 mbyte/r2q = 12.5 MByte > 60.000. So get

Warnings. But can overrule the quantum:

TC class Add dev eth0 parent 1:1 classid 1:11 HTB rate 128kbit burst 2k

Quantum 60000



Quantum was used when 2 classes was getting more bandwidth then the rate. So

It ' s only important for sharing the remaining bandwidth. In the case, each

Class may send quantum bytes.

TC HTB r2q