Question about ath10k throughput

[Shu, Nick]

Hi, Group:
I'm doing throughout measurement on QCA9880 chip, running ath10k 3.17 driver with firmware.
I'm able to set channel width to 80MHz, enabled all three streams, MCS index to 9 for max. data throughput.
I verified all initial setting are correct.
But when test starts, MCS dropped (as the results of packet error?).
Is there any app command to send to driver to lock the MCS index during the test, so we can see better throughput?
What is the best practical number we can get for ath10k chip? 800? 900?

Thanks!
Nick Shu
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