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Which is true
cake is only meant , wired as it’s ping sensitive more which doesn’t mean one cannot use it
just that with all things equal, cake doesn’t account for the bad wifi unless it’s specific for lower bandwidth
good to see folks chiming in
I learned this only recently. BTW, the following is an interesting learning for me. Initially I thought cake-autorate can be used to deal with wireless bufferbloat, but apparently I was wrong.
https://github.com/lynxthecat/cake-autorate/issues/274#issuecomment-2034550854
Yeah, I think this is sub-optimal. Assuming your trie internet/WAN delay is well behaved you need a single cake instance per direction to control internet bufferbloat, and then deal with WiFi locally. The problems with WiFi are myriad:
a) WiFi is half duplex, and hence you need to run cake-autorate on all wirelessly connected devices and the AP
b) internet latency targets are unlikely to be ideal for a WiFi traffic shaper and vice versa
c) active measurements even with small ICMP packets waste an airtime slot, so have considerable side effects, especially if you consider a larger set of wifi connected devices...
In short, I would look for an airtime fairness/AQL capable WiFi-AP, that should deal with the AP to station bufferbloat decently. For the other direction you would need to fix the station's WiFi stack somehow... or hope that stations send far less than they receive...
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The following is a good summary as well.
https://forum.openwrt.org/t/how-openwrt-vanquishes-bufferbloat/189381
On Wireless Connections
Since OpenWrt is an access point, it can manage all the traffic flowing toward the many devices ("stations") that it serves. The "OpenWrt Wi-Fi Driver" uses the following mechanisms to reduce latency:
Individual transmit queues for each wireless station/client. Each queue ues fq_codel to control the amount of data queued for that station.
Airtime Fairness (ATF) to give each wireless client a fair share of the airtime as opposed to the number of bytes sent/received with ordinary Wi-Fi drivers. This ensures a low-rate (slow) station does not use up all the airtime (the so-called "WiFi anomaly"). ATF uses round-robin scheduling of all active stations to ensure they each use only their fair share of the available airtime.
Airtime Queue Limits (AQL) to prevent the chip hardware from queueing too much data for any one wireless station. Many wireless chipsets have significant (unnecessary) queueing. By default, AQL analyzes the actual bit rate for that station and ensures that no more than 12 msec of data is queued for it.
Modern OpenWrt supports the Wi-Fi driver for certain chipsets (Note: mainly mt76 and ath11k, in the future maybe ath12k).
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