SQM best practices for LTE 4G or WISP connections with variable DL/UL speed

I found good tutorial for enabling SQM on Openwrt here https://openwrt.org/docs/guide-user/network/traffic-shaping/sqm
I tested it and it can significantly lower the buffer bloat side effects. But can this optimisation be done also on wireless internets like LTE 4G or on a wireless internet service provider lines (wifi) where download and upload spees changes depending on the time? For instance I have an LTE connection and I can reach 25 mbit/s but then there are times when a lot of people use LTE and my speed can be something like 7 mbit/s.
So is there some working SQM optimisation without limiting the DL/UL speed? Or is it completely out of the scope and the SQM needs specifying UL/DL speed limits?

Unfortunately SQM needs reasonably fixed rates to work properly. You could have a look at evenroute's iqrouter, which is based on OpenWrt and does repeated automated speedtests and adjusts the shaper bandwidth according to the results, Whether that is reactive enough for LTE I have no clue, but it might be worth a shot. Also the Gargoyle firmware (also OpenWrt based) has an automatic mode where it tries to adjust the download bandwidth (but it requires assured upload bandwidth, IIRC).

Good luck.

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That is only acceptable of his dataplan is unlimited, doing constant speedtests will devour any set dataplan. The best thing the op could do is put a much lower fixed value, for example if you are sure your lte speed can reach 10mb daytime then set 5mb, worse peak times are usually around 17:00 - 21:00, at that time range if you get 10mb then expect 2mb.

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