The optional RATEMPU parameter (where "MPU" stands for "minimum packet unit") limits the packet rate by making packets smaller than MPU in size consume HTB tokens. With it, small packets can be accounted as larger ones and limited by TOTALRATE and RATE parameters. Approximately, the maximum packets per second rate can be calculated as TOTALRATE / RATEMPU.
This parameter has the following syntax: <NIC>:<network_class>[:<MPU_in_bytes_per_packet>]. If the part <MPU_in_bytes_per_packet> is omitted, the default value of 1000 bytes is used. Multiple entries can be separated by spaces, e.g., enp0s5:1:2000 enp0s6:2:4000. To set the RATEMPU parameter for all known Ethernet devices set <NIC> to an asterisk (*). For example, to set the minimal packet size to 2 Kb for network class 1 on all the Ethernet adapters on the node, change the value to *:1:2000.
