High throughput ingress datapath for a virtual machine

A non-transitory machine readable medium storing a program for execution by at least one processing unit, the program for forwarding data messages to a machine executing on a host computer, the machine having an associated virtual network interface controller (VNIC), the program comprising sets of instructions for:

• storing, in a first set of buffer data stores associated with the VNIC, a first plurality of data messages retrieved from a queue of the VNIC associated with the machine;
• and
• after the first set of buffer data stores reaches a threshold congestion level, storing, in a
• second set of buffer data stores associated with the VNIC, a second plurality of data messages
• retrieved from the VNIC queue,
• wherein:
• a set of one or more processes executing on the machine retrieves the data messages from the first and second sets of buffer data stores;
• and
• when the first plurality of data messages is stored in the first set of buffer data stores, the
• buffer data stores of the first set are designated as active buffer data stores and the buffer data
• stores of the second set are designated as standby buffer data stores, and
• when the second plurality of data messages is stored in the second set of buffer data stores, the buffer data stores of the second set are designated as active buffer data stores and the buffer data stores of the first set are designated as standby buffer data stores.