Need help setting up QoS

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Occasional Visitor
I have an RT-AC66U running Merlin FW (Johns Fork).

I have a quite common problem :
On the network I have a PC where I play an online game (Path of Exile), which I'd like to always take priority over anything else.
There is also a TV with a Firestick, which my wife uses to watch tv shows.

I tried to set a single QoS rule with as source my MAC address, blank destination port, protocol tcp\udp, "transfered" blank, and priority High.
The priority High is defined with 40% minimum reserved upload and 40% minimum reserved download bandwidth.

As of my understanding, anything else should get a Low priority, which has only 5% min reserved upload and 10% download bandwidth.

The problem is, in game I still have problems with lag spikes every few seconds while the damned firestick is downloading damned tv shows (ping remains "stable" in the 40-50ms range, and then suddenly goes to 250-300ms for a second (every few seconds)).
If the firestick is turned off, the game runs without problems, so it is not a problem of the game servers.

I also tried to set a rule with only destination port 6112 (which should be the one used by the game on remote), with the same effect.

My internet total bandwidth is not the greatest, I have a maximum of 2.4 Mb\s Upload and 16 Mb\s Download.

Save my marriage.


Part of the Furniture
Save my marriage.
Watch the TV shows with your wife instead of gaming.

Otherwise, you may not be limiting your bandwidth enough in the QoS settings. Whatever your Mb values, lower them some more.


Part of the Furniture
Do you mean the ones entered in the main QoS page ? I got those values from Speedtest, they should be accurate. I will try lower them anyways.
Yes, those ones. They must be slightly lower than your actual speeds in order to ensure the router manages the flow of data to the ISP where the bufferbloat occurs. If your actual ISP speeds ever fluctuate below what you’ve entered on the QoS page, then you’re no longer in control of bufferbloat.

Sacrifice bandwidth for the sake of latency and no-bloat. Granted, you don’t have a lot of bandwidth to work with, especially on the upload side. Gaming with less than 3 Mb can be problematic.

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