A computer system for flexible load balancing on a multipath network includes a processor that implements a multipath transport protocol as a transport layer of a network stack, a load balancer that distributes network traffic across a plurality of paths, and a congestion controller in communication with the load balancer. The congestion controller determines parameters for a message based on information received from the load balancer. A scheduler included in the load balancer selects a load balancing algorithm from a plurality of load balancing algorithms based on the parameters of the message received from the congestion controller and, based on the selected load balancing algorithm, determines a timing and a path for the message to be sent to the transport layer.

In one embodiment, a network device includes a network interface to receive packets over a packet data network, packet processing circuitry to manage a multiplex network receive queue, and including a policer to provide queue fairness for a plurality of network flows competing for access to the multiplex network receive queue, and including meters to label the received packets, and selectively operate in (a) a two-level mode with two-levels of the meters, and (b) a single-level mode with a single one of the meters, and queueing logic to add some of the received packets to the multiplex network receive queue and drop others of the received packets responsively to labelling of the packets by the meters.