Network interface card rate limiting

A programmable network interface controller (NIC) comprising:

• a non-transitory storage device having embodied therein instructions representing a data packet rate limiting routine;
• and
• one or more processors coupled to the non-transitory storage device and operable to execute the data packet rate limiting routing to perform a method comprising:
• receiving, data packets from a network, wherein the NIC is coupled to a host central processing unit (CPU) of a network appliance through a bus system;
• monitoring a status of the host CPU, including:
• responsive to receiving a data packet, notifying the host CPU the data packet is available for processing by the host CPU, by issuing an interrupt to the host CPU;
• disabling the interrupt;
• measuring a time period during which the interrupt remains disabled by monitoring the interrupt;
• and
• determining the host CPU is busy when the time period exceeds a threshold;
• setting a rate limiting mode indicator based on the status;
• when the rate limiting mode indicator indicates rate limiting is inactive, then transmitting the received data packets from the NIC to the host CPU for processing;
• and
• when the rate limiting mode indicator indicates rate limiting is active, then performing rate limiting by temporarily stopping or slowing transmission of the received data packets from the NIC to the host CPU for processing.

A method comprising:

• receiving, by a network interface card (NIC), data packets from a network, wherein the NIC is coupled to a host central processing unit (CPU) of a network appliance through a bus system;
• monitoring, by the NIC, a status of the host CPU;
• setting, by a first process running on the NIC, a rate limiting mode indicator based on the status;
• when the rate limiting mode indicator indicates rate limiting is inactive, then transmitting, by a second process running on the NIC, the received data packets to the host CPU for processing;
• and
• when the rate limiting mode indicator indicates rate limiting is active, then performing, by the NIC, rate limiting by temporarily stopping or slowing transmission of the received data packets to the host CPU for processing.

A programmable network interface controller (NIC) comprising:

• a non-transitory storage device having embodied therein instructions representing a data packet rate limiting routine;
• and
• one or more processors coupled to the non-transitory storage device and operable to execute the data packet rate limiting routing to perform a method comprising:
• receiving data packets from a network, wherein the NIC is coupled to a host central processing unit (CPU) of a network appliance through a bus system;
• monitoring a status of the host CPU;
• setting, by a first process associated with the data packet rate limiting routine, a rate limiting mode indicator based on the status;
• when the rate limiting mode indicator indicates rate limiting is inactive, then transmitting, by a second process associated with the data packet rating limiting routine, the received data packets from the NIC to the host CPU for processing;
• and
• when the rate limiting mode indicator indicates rate limiting is active, then performing rate limiting by temporarily stopping or slowing transmission of the received data packets from the NIC to the host CPU for processing.