N66U ping times flake out with Merlin

[DJK]

Hello everyone. I've been running Merlin on my N66U for a long time (currently at 380.65), and I've noticed that occasionally, something will happen that causes significant latency on my wifi network, and the most prominent symptom is that ping times will spike to 1000ms, then slowly fall by a few ms with each packet, until they get down to single digit ping times, at which point they spike back up to 1000ms, and the cycle repeats.

I've not been able to pinpoint it to any direct cause. To fix it, I log into the router GUI (which is quite slow due to all of the latency), and restart wifi. To do this, as a shortcut, I go to the professional tab under wireless and just click apply, which (among other things) issues a wifi restart. I suppose I should really just turn on SSH and do it that way. *shrug*

I'm attaching a couple of screenshots, one that shows the behavior:

And one that shows what happens as I restart the wifi. You can see it drop, and then ping times pretty quickly return to normal:

If anyone has any ideas as to what might cause this, particularly if it's a setting on my end, I'd love to hear about it. Thanks!

 

[Nullity]

Which WiFi clients?

I've experienced this as well but it was usually caused by the client, like buggy drivers or power-saving features.

Have you reset the RT-N66U to the Factory Defaults?

 

[DJK]

I haven't factory reset yet, but I probably should...I don't recall that I've ever done that, really, and given how long I've had the router, it might not hurt.

The other thing I've always had a hunch on, but never been able to prove, is some correlation between older iPhone devices and this behavior. I swear I've seen it more when my kids have had a friend over, and so I always wondered if someone had an older iPhone that didn't play nicely. Seems odd that it would affect the entire network, and it would be great to know what it triggers to cause this, but again, this is just complete speculation. I have no hard evidence that this is what's causing it.

 

[DJK]

Oh, I didn't answer your first question. When I see this, it appears to be nearly all wireless clients on a particular band, but again, I haven't verified this yet. I can't recreate the condition on demand, so I'll have to wait until the next time it crops up and verify which clients are also seeing this behavior.

 

[Nullity]

You could possibly try disabling WiFi frame aggregation and/or certain power-saving features. I would be cautious though, especially since you are just guessing at what might be causing the problem.

I think Factory Resetting is the best thing to try first.

 

[heysoundude]

https://routerguide.net/generic-optimization-guides/ is a great place to go and tweak your router for your network...after the factory reset.
helped me tune mine up rather nicely...