3.9. net_prio

The Network Priority (net_prio) subsystem provides a way to dynamically set the priority of network traffic per each network interface for applications within various cgroups. A network's priority is a number assigned to network traffic and used internally by the system and network devices. Network priority is used to differentiate packets that are sent, queued, or dropped. The tc command may be used to set a network's priority (setting the network priority via the tc command is outside the scope of this guide; for more information, refer to the tc man page).

Typically, an application sets the priority of its traffic via the SO_PRIORITY socket option. However, applications are often not coded to set the priority value, or the application's traffic is site-specific and does not provide a defined priority.

Using the net_prio subsystem in a cgroup allows the administrator to assign a process to a specific cgroup which defines the priority of outgoing traffic on a given network interface.

The following tunable parameters are available for net_prio: