Hello.

If you don't know how to shape gigabits via HTB and u32 flow filters, maybe for you will be useful to sc - this is tool for ISP, do all work for you.
Hope this helps.

I get the part about matching with tc-filter and the u32 selector (as intuitive as that is :), but am not sure of the action the filter needs to take. However, I do see the example towards the bottom of the tc-u32 man page where a hash table is created and filters move packets into the right buckets. Perhaps it will be eventually decipherable from this… :)