Uplink congestion mitigation
System and techniques for uplink congestion mitigation are described herein. A packet acknowledgement (ACK) rate may be measured in a transmission queue to detect when the ACK rate exceeds a threshold. In response to the ACK rate exceeding the threshold, ACKs may be removed from the transmission queue in accordance with a time-based uplink reduction function. ACKs that remain in the transmission queue after ACKs are removed in accordance with the time-based uplink reduction function may then be transmitted.
1. An apparatus for uplink congestion mitigation, the apparatus included in a communication device, the apparatus comprising:
a buffer to store a transmission queue; and
processing circuitry to:
measure a packet acknowledgement (ACK) rate in a transmission queue to detect when the ACK rate exceeds a threshold, wherein the ACK rate is calculated by:
R
=
{
R
*
max
(
0
,
(
T
-
d
)
)
+
min
(
d
,
T
)
r
}
T
T
where R is the ACK rate, T is a measurement window, d is a measurement interval since a last sample, and r is an instant ACK rate;
remove, in response to the ACK rate exceeding the threshold, ACKs from the transmission queue in accordance with a time-based uplink reduction function; and
initiate transmission ACKs that remain in the transmission queue after ACKs are removed in accordance with the time-based uplink reduction function.
2. The apparatus of claim 1 , wherein the time-based uplink reduction function removes a percentage of ACKs to meet a percentage that corresponds to the threshold.
3. The apparatus of claim 1 , wherein multiple traffic flows deposit ACKs into the transmission queue.
4. The apparatus of claim 3 , wherein, to remove the ACKs from the transmission queue, the processing circuitry removes ACKs from the multiple traffic flows in proportion to ACKs contributed by each of the multiple traffic flows.
5. The apparatus of claim 1 , wherein the ACKs are transmission control protocol (TCP) ACKs.
6. The apparatus of claim 5 , wherein multiple TCP streams deposit ACKs into the transmission queue, the multiple TCP streams including a TCP slow start flow.
7. The apparatus of claim 6 , wherein ACKs from the TCP slow start flow are not removed from the transmission queue.
8. The apparatus of claim 2 , wherein the time-based uplink reduction function includes a smoothing factor to smooth ACK bursts over multiple uplink grant intervals.
9. A method for uplink congestion mitigation, the method comprising:
measuring a packet acknowledgement (ACK) rate in a transmission queue to detect when the ACK rate exceeds a threshold, wherein the ACK rate is calculated by:
R
=
{
R
*
max
(
0
,
(
T
-
d
)
)
+
min
(
d
,
T
)
r
}
T
T
where R is the ACK rate, T is a measurement window, d is a measurement interval since a last sample, and r is an instant ACK rate;
removing, in response to the ACK rate exceeding the threshold, ACKs from the transmission queue in accordance with a time-based uplink reduction function; and
transmitting ACKs that remain in the transmission queue after ACKs are removed in accordance with the time-based uplink reduction function.
10. The method of claim 9 , wherein the time-based uplink reduction function removes a percentage of ACKs to meet a percentage that corresponds to the threshold.
11. The method of claim 9 , wherein multiple traffic flows deposit ACKs into the transmission queue.
12. The method of claim 11 , wherein removing the ACKs from the transmission queue includes removing ACKs from the multiple traffic flows in proportion to ACKs contributed by each of the multiple traffic flows.
13. The method of claim 9 , wherein the ACKs are transmission control protocol (TCP) ACKs.
14. The method of claim 13 , wherein multiple TCP streams deposit ACKs into the transmission queue, the multiple TCP streams including a TCP slow start flow.
15. The method of claim 14 , wherein ACKs from the TCP slow start flow are not removed from the transmission queue.
16. The method of claim 10 , wherein the time-based uplink reduction function includes a smoothing factor to smooth ACK bursts over multiple uplink grant intervals.
17. At least one non-transitory machine readable medium including instructions for uplink congestion mitigation, the instructions, when executed by processing circuitry, cause the processing circuitry to perform operations comprising:
measuring a packet acknowledgement (ACK) rate in a transmission queue to detect when the ACK rate exceeds a threshold, wherein the ACK rate is calculated by:
R
=
{
R
*
max
(
0
,
(
T
-
d
)
)
+
min
(
d
,
T
)
r
}
T
T
where R is the ACK rate, T is a measurement window, d is a measurement interval since a last sample, and r is an instant ACK rate;
removing, in response to the ACK rate exceeding the threshold, ACKs from the transmission queue in accordance with a time-based uplink reduction function; and
transmitting ACKs that remain in the transmission queue after ACKs are removed in accordance with the time-based uplink reduction function.
18. The at least one machine readable medium of claim 17 , wherein the time-based uplink reduction function removes a percentage of ACKs to meet a percentage that corresponds to the threshold.
19. The at least one machine readable medium of claim 17 , wherein multiple traffic flows deposit ACKs into the transmission queue.
20. The at least one machine readable medium of claim 19 , wherein removing the ACKs from the transmission queue includes removing ACKs from the multiple traffic flows in proportion to ACKs contributed by each of the multiple traffic flows.
21. The at least one machine readable medium of claim 17 , wherein the ACKs are transmission control protocol (TCP) ACKs.
22. The at least one machine readable medium of claim 21 , wherein multiple TCP streams deposit ACKs into the transmission queue, the multiple TCP streams including a TCP slow start flow.
23. The at least one machine readable medium of claim 22 , wherein ACKs from the TCP slow start flow are not removed from the transmission queue.
24. The at least one machine readable medium of claim 18 , wherein the time-based uplink reduction function includes a smoothing factor to smooth ACK bursts over multiple uplink grant intervals.