I have been playing around with QOS and have given up. It doesn't decrease latency spikes in the slightest
I use QoS successfully here on Merlin LTS fork . I established my configuration based on a discussion I read on the Freshtomato-mips forum.
My router is an RT-N66U.
I adjusted the "Up Bandwidth" to 75% of the minimum I observed (after several tests) and the "Down Bandwidth" to 85% of the minimum also observed. It is also these settings that give me (after many tests) the lowest average Bufferbloat results in ms, in the detailed results of "dslreports":
http://www.dslreports.com/speedtest/50662106
I have a constant rating of "A+" since I made these adjustments.
List of standards specified by the user:
TCP/UDP, DST port 1-5070, Transferred 0-1kb, class1 (Highest)
any, MAC address (VOIP interface), class2 (High)
TCP/UDP, DST port 1-5070, Transferred 0-64kb, class2 (High)
TCP/UDP, DST port 1-65535, Transferred 0-512kb, class3 (Average)
TCP/UDP, DST port 1-65535, Transferred 0-1024kb, class4 (Low)
TCP/UDP, DST port 1-65535, Transferred 1024kb+ class5 (Lowest)
Download and transmission limits:
1, 15%, 100%
2, 5%, 100%
3, 5%, 100%
4, 5%, 100%
5, 5%, 95% (Set as Default)
(same for both outbound and inbound)