On Sunday, 19 January 2025 04:20:46 CET Andrew Strohman wrote:
In my case, my 2.4ghz radio driver uses minstrel for rate control, so throughput estimates are derived using sta_get_expected_throughput(). For me, this estimation is chronically an over estimate. The 5ghz radio does rate control in hardware, so we cannot use the sta_get_expected_throughput() method for it.
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I'm suggesting that we make an effort to make the throughput calculation method consistent across radios.
That's certainly an interesting observation but seems irrelevant to the patch proposal you are responding to. Feel free to propose a code change that aims to unify the chosen metric source across all radios on the same AP. With the current implementation, this is left to the administrator.
After this patch, it means that the throughput estimation for 5ghz stas/neighbors in my network will be derived by examining an exponentially weighted average of tx rate with consideration of tx failures.
After this patch, the 11s throughput estimation is available as a metric source. That's all. The patch does not even attempt to address your concern.
If this new fallback method results in in more similar results to sta_get_expected_throughput(), then my problem will be lessened, possibly to the point of my network preferring 5ghz (as should be done).
Even if the 11s metric source accidentally provides a similar metric in your test setup, there is no guarantee it always will. Again, your are conflating your desired outcome with a random patch which isn't trying to do what you want it to do.
OK, thanks. If you're confident that sta_get_expected_throughput() returns a result that reflects the recent or likely external contention on the operating frequency, that's good to know.
Feel free to read up on how minstrel arrives at the expected throughput.
Like I noted in my original message, I was seeing the estimated throughput as 150Mb/s for the sta_get_expected_throughput() method, while really only able to tx at ~25Mb/s.
Am I right assuming this '~25Mb/s' was measured using iperf or some other speed test? The numbers minstrel provides are in a completely different ball park and can not be compared to WiFi throughput numbers. You are also not taking into account what I have already explained why getting 'accurate' throughput numbers is meaningless.
I'll now be debugging under the assumption that something else causes overestimation in my case.
You are still stuck on over / under estimation. In this email alone you are mentioning it 6 times. Whether there is over or under estimation is irrelevant. Consistency is relevant.
Cheers, Marek