Tool/software:
I need to set the MTU to 9000. This is a requirement when transmitting visual images. However, when I attempted to set this value in the system, it was restricted. How should I modify the kernel configuration to achieve the goal?
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Tool/software:
I need to set the MTU to 9000. This is a requirement when transmitting visual images. However, when I attempted to set this value in the system, it was restricted. How should I modify the kernel configuration to achieve the goal?
I found in am65-cpsw-nuss.c the lines "#define AM65_CPSW_MAX_PACKET_SIZE 2024" and "port->ndev->max_mtu = AM65_CPSW_MAX_PACKET_SIZE - (VLAN_ETH_HLEN + ETH_FCS_LEN);"
I should only need to change "2024" to "9022", but I'm not sure if the hardware supports it or if there are any issues. Please let me know. Thank you.
Hi,
I found in am65-cpsw-nuss.c the lines "#define AM65_CPSW_MAX_PACKET_SIZE 2024" and "port->ndev->max_mtu = AM65_CPSW_MAX_PACKET_SIZE - (VLAN_ETH_HLEN + ETH_FCS_LEN);"
I should only need to change "2024" to "9022", but I'm not sure if the hardware supports it or if there are any issues. Please let me know. Thank you.
Hardware can't support a frame size beyond 2024. So, from the driver side, we are limiting the maximum MTU to 2024.
You have to enable frame fragmentation from the network stack, so that all frames submitted to the Hardware will be limited to the MTU.
Best Regards,
Sudheer
Hi,
So, how should I enable frame fragmentation within the network stack?
Please refer to GSO (Generic Segmentation Offload), which can be enabled using ethtool options.
https://man7.org/linux/man-pages/man8/ethtool.8.html
Note: On the Sender side itself, we have to enable GSO to fragment the large frames beyond the MTU.
Best Regards,
Sudheer