47bc081e76
This adds a patch that introduces airtime fairness scheduling to ath9k, which can significantly improve network efficiency in mixed-rate environments. Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> Signed-off-by: Felix Fietkau <nbd@nbd.name>
35 lines
1.5 KiB
Diff
35 lines
1.5 KiB
Diff
From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk>
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Date: Mon, 5 Dec 2016 13:27:37 +0200
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Subject: [PATCH] ath9k: Introduce airtime fairness scheduling between stations
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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This reworks the ath9k driver to schedule transmissions to connected
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stations in a way that enforces airtime fairness between them. It
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accomplishes this by measuring the time spent transmitting to or
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receiving from a station at TX and RX completion, and accounting this to
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a per-station, per-QoS level airtime deficit. Then, an FQ-CoDel based
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deficit scheduler is employed at packet dequeue time, to control which
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station gets the next transmission opportunity.
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Airtime fairness can significantly improve the efficiency of the network
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when station rates vary. The following throughput values are from a
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simple three-station test scenario, where two stations operate at the
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highest HT20 rate, and one station at the lowest, and the scheduler is
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employed at the access point:
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Before / After
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Fast station 1: 19.17 / 25.09 Mbps
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Fast station 2: 19.83 / 25.21 Mbps
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Slow station: 2.58 / 1.77 Mbps
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Total: 41.58 / 52.07 Mbps
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The benefit of airtime fairness goes up the more stations are present.
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In a 30-station test with one station artificially limited to 1 Mbps,
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we have seen aggregate throughput go from 2.14 to 17.76 Mbps.
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Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
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Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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