Thanks for the help.
I am using TP link C2600.
I think I made a mistake last night by testing using LAN connection. I switched to WIFI this morning and it is much better:
Before I enable sqm:
After I enable sqm:
I then increased download from 59000 to 70000, upload from 9000 to 10000, and tested again:
So it looks much better now. Will WIFI user experience be a lot different speed wise?