Adjusting the Size of Receive Buffer

Purpose

The rx_buff parameter controls the receive buffer size with four configurable options: 2 KB, 4 KB, 8 KB, or 16 KB. The value must be a power of 2 to ensure contiguous memory allocation.

The Hi1822 NIC defaults to a 2 KB rx_buff setting. When processing 64 KB aggregated packets, this buffer size triggers memory fragmentation due to the need for non-contiguous memory blocks. Increasing rx_buff to 8 KB minimizes the allocation requirements, thereby optimizing memory efficiency and boosting data transfer throughput.

Procedure

1. Check the value of rx_buff. The default value is 2.

   1	cat /sys/bus/pci/drivers/hinic/module/parameters/rx_buff

2. Add the hinic.conf file to the /etc/modprobe.d/ directory and change the rx_buff value to 8.

   1	options hinic rx_buff=8

3. Remount the hinic driver for the configuration to take effect.

   1 2	rmmod hinic modprobe hinic

4. Check whether the configuration is successful.

   1	cat /sys/bus/pci/drivers/hinic/module/parameters/rx_buff

   If the parameter value is updated to 8, the configuration is successful.