I am currently using this:
iptables -t mangle -A PREROUTING -j DSCP --set-dscp-class CS0
iptables -t mangle -A PREROUTING -p icmp -j DSCP --set-dscp-class EF
iptables -t mangle -A POSTROUTING -p icmp -j DSCP --set-dscp-class EF
iptables -t mangle -A FORWARD -p icmp -j DSCP --set-dscp-class EF
iptables -t mangle -A PREROUTING -p udp --match multiport --sport 3658:3659,3074:3075,3478:3479,9305:9308,6672 -j DSCP --set-dscp-class EF
iptables -t mangle -A PREROUTING -p udp --match multiport --dport 3658:3659,3478:3480,3074:3075,9305:9308,6672 -j DSCP --set-dscp-class EF
iptables -t mangle -A POSTROUTING -p udp --match multiport --sport 3658:3659,3478:3480,3074:3075,9305:9308,6672 -j DSCP --set-dscp-class EF
iptables -t mangle -A POSTROUTING -p udp --match multiport --dport 3658:3659,3478:3480,3074:3075,9305:9308,6672 -j DSCP --set-dscp-class CS6
iptables -t mangle -A FORWARD -p udp --match multiport --sport 3658:3659,3478:3480,3074:3075,9305:9308,6672 -j DSCP --set-dscp-class EF
iptables -t mangle -A FORWARD -p udp --match multiport --dport 3658:3659,3478:3480,3074:3075,9305:9308,6672 -j DSCP --set-dscp-class EF
It seems to be the best.
If you play in wifi, in POSTROUTING dport, use CS6.
In cable use all with EF.
QoS Gargoyle:
I am satisfied now
One thing, Battlefield 1 for example, uses ports 14000-14016, but the only port actually being used is 3659, as are many EA games. And the torrent here, used port 14002. So attention.
You can use Wireshark to view DSCP tags.