[FS#44] Ath9k - TX performance regression on greater coverage settings

[LEDE Bugs]

The following task has a new comment added:

FS#44 - Ath9k - TX performance regression on greater coverage settings
User who did this - Koen Vandeputte (xback)

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Hi Bluse,
Hi Stoffel,

Thanks again for your time looking into this.

When I encountered this "bug", this was the first part I checked :)
This patch has been applied in **__both__** builds (barrierbreaker & trunk)

So it's not the reason for the regression.

I'll upload the mac80211 (incl ath9k) from both my builds tomorrow and provide a link.


I've checked and compared the full ath9k driver to search for the rootcause,
and added some prints in xmit.c (ath_tx_start()) where frames get scheduled in the aggregation queue.

When this bug occurs (coverage increases) mac80211 is re-calling this functions at a lower pace.
Every frame entering gets scheduled in the aggregation queue, but it only contains 1 .. 2 frames max before the session time ends and the frames in this queue get transmitted.


Thanks again,

Koen
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=44#comment181