Issue description
The displayed speed rate limitation is different from the configuration, just as the below information shows:
<dev_hq>display cpu-defend policy xx
name :xx
related slot:<0>
configuration:
car packet-type arp-request: cir(40) cbs(10000)
...
<dev_hq> display cpu-defend rate packet-type arp-request
Info: Please wait for a moment....
Cpu-defend rate on slot 0:
-------------------------------------------------------------------------------
Packet Type Pass(bps) Drop(bps) Pass(pps) Drop(pps)
-------------------------------------------------------------------------------
arp-request 31530 4432 33 12
-------------------------------------------------------------------------------
Solution
When calculating the speed limit of the flow rate, the device includes the frame gap and the preamble by default, that is, the traffic rate is not only including the data packet traffic. Shorter packets will be more affected by the frame clearance and preamble than larger ones.
The rate of speed limit can be configured by qos-car exclude-interframe and qos-shaping exclude-interframe, excluding the frame gap and preamble of the message, thereby improving the accuracy of the speed limiting function.
In fact, our device is working fine, there is just a different calculation method.
