Method and apparatus for managing traffic in a network
The present invention relates to a traffic manager ( 1 ) and a method for a traffic manager ( 1 ), the method comprising the step of reading a first data packet (D 1 -D D ) comprised in a first queue (Q I -Q Q ) based on a scheduling priority (SP), the scheduling priority (SP) being determined: —at least partly on a configured priority of the first queue (Q I -Q Q ), —at least partly on a first meter value (MV l -MV M ) of a first meter (Mi-MM) associated with the first queue (Q I -Q Q ); and—at least partly on a second meter value (MV l -MV M ) of a second meter (M l -M M ) associated with a first scheduling node (N I -N N ); the first scheduling node being a parent node of the first queue.
1. A method for a traffic manager to manage traffic in a network, wherein the traffic manager comprises a hierarchical scheduler, a plurality of queues, and a plurality of scheduling nodes, the method comprising:
reading a first data packet from a first queue of the plurality of queues based on a scheduling priority of the first queue, wherein the scheduling priority corresponds to a priority at which data packets in respective queues are processed, and wherein the scheduling priority of the first queue is based on:
a configured priority of the first queue, wherein the configured priority corresponds to a predetermined priority assigned to the first queue;
a value of a first meter configured to track an amount of data in the first queue; and
a value of a second meter configured to track an amount of data in a first scheduling node of the plurality of scheduling nodes, the first scheduling node being a parent node of the first queue; and
propagating the scheduling priority of the first queue to the first scheduling node;
selectively changing a scheduling priority of the first scheduling node based on (i) a predetermined priority if the first scheduling node is not assigned a dynamic priority, and (ii) the scheduling priority of the first queue propagated to the first scheduling node if the first scheduling node is assigned the dynamic priority, wherein the dynamic priority indicates that the scheduling priority of the first scheduling node is changeable in accordance with the propagated priority; and
reading the first data packet from the first scheduling node based on the changed scheduling priority of the first scheduling node.
2. A method according to claim 1 , further comprising using the first meter and the second meter to dynamically change respective priority levels of the first queue and the first scheduling node between:
a high priority level when the value of the first meter and the value of the second meter are equal to or higher than a first limit value and a second limit value, respectively, and
a low priority level when the value of the first meter and the value of the second meter are lower than the first limit value and the second limit value, respectively.
3. A method according to claim 1 , further comprising:
decreasing the value of the first meter and the value of the second meter according to an amount of bits of the first data packet if the first data packet is read from the first queue; and
periodically increasing the value of the first meter and the value of the second meter by a meter value amount.
4. A method according to claim 1 , further comprising using the first meter and the second meter to dynamically change respective priority levels of the first queue and the first scheduling node between:
a low priority level when the value of the first meter and the value of the second meter are higher than a first limit value and a second limit value, respectively, and
a high priority level when the value of the first meter and the value of the second meter are equal to or less than the first limit value and the second limit value.
5. A method according to claim 4 , further comprising:
increasing the value of the first meter and the value of the second meter according to an amount of bits of the first data packet if the first data packet is read from the first queue; and
periodically decreasing the value of the first meter and the value of the second meter by a meter value amount.
6. A method according to claim 1 , further comprising reading the first data packet based on:
a first shaper value of a first shaper associated with the first queue; and
a second shaper value of a second shaper associated with the first scheduling node.
7. A method according to claim 6 , further comprising:
decreasing the first shaper value and the second shaper value according to an amount of bits of the first data packet if the first data packet is read from the first queue; and
periodically increasing the first shaper value and the second shaper value by a shaper value amount.
8. A method according to claim 6 , further comprising:
increasing the first shaper value and the second shaper value according to an amount of bits of the first data packet if the first data packet is read from the first queue; and
periodically decreasing the first shaper value and the second shaper value.
9. A traffic manager, comprising:
a hierarchical scheduler;
a plurality of queues; and
a plurality of scheduling nodes, the traffic manager being configured to read a first data packet from a first queue of the plurality of queues based on a scheduling priority of the first queue, wherein the scheduling priority corresponds to a priority at which data packets in respective queues are processed, and wherein the scheduling priority is based on:
a configured priority of the first queue, wherein the configured priority corresponds to a predetermined priority assigned to the first queue;
a value of a first meter configured to track an amount of data in the first queue; and
a value of a second meter configured to track an amount of data in a first scheduling node of the plurality of scheduling nodes, the first scheduling node being a parent node of the first queue,
wherein the first queue is configured to propagate the scheduling priority of the first queue to the first scheduling node, and
wherein the first scheduling node is configured to selectively change a scheduling priority of the first scheduling node based on (i) a predetermined priority if the first scheduling node is not assigned a dynamic priority, and (ii) the scheduling priority of the first queue propagated to the first scheduling node if the first scheduling node is assigned a dynamic priority, wherein the dynamic priority indicates that the scheduling priority of the first scheduling node is changeable in accordance with the propagated priority.
10. A traffic manager according to claim 9 , wherein the first meter and the second meter are configured to dynamically change respective priority levels of the first queue and the first scheduling node between:
a high priority level when the value of the first meter and the value of the second meter are equal to or higher than a first limit value and a second limit value, respectively, and
a low priority level when the value of the first meter and the value of the second meter are lower than the first limit value and the second limit value, respectively.
11. A traffic manager according to claim 10 , further being configured to:
decrease the value of the first meter and the value of the second meter according to an amount of bits of the first data packet if the first data packet is read from the first queue; and
periodically increase the value of the first meter and the value of the second meter.
12. A traffic manager according to claim 9 , wherein the first meter and the second meter are configured to dynamically change respective priority levels of the first queue and the first scheduling node between:
a low priority level when the value of the first meter and the value of the second meter are higher than a first limit value and a second limit value, respectively, and
a high priority level when the value of the first meter and the value of the second meter are equal to or less than the first limit value and the second limit value, respectively.
13. A traffic manager according claim 12 , further being configured to:
increase the value of the first meter and the value of the second meter according to an amount of bits of the first data packet if the first data packet is read from the first queue; and
periodically decrease the value of the first meter and the value of the second meter.
14. A traffic manager according to claim 9 , further being configured to read the first data packet based on:
a first shaper value of a first shaper associated with the first queue; and
a second shaper value of a second shaper associated with the first scheduling node.
15. A traffic manager according to claim 14 , further being configured to:
decrease the first shaper value and the second shaper value according to an amount of bits of the first data packet if the first data packet is read from the first queue; and
periodically increase the first shaper value and the second shaper value by a shaper value amount.
16. A traffic manager according to claim 14 , further being configured to:
increase the first shaper value and the second shaper value according to an amount of bits of the first data packet if the first data packet is read from the first queue; and
periodically decrease the first shaper value and the second shaper value by a shaper value amount.