Asus RT-N68U high cpu usage during game scan

[Nexy]

EDIT: AC68U, not N68U as per title, I can't change it.

I'll try to provide as much info here as I can, if I'm missing anything, please do let me know, but it should be somewhat self-explanatory.

The problem I'm having, when one of my games (Dark & Light), does a scan for unofficial servers, the CPU usage on the Asus (running Merlin 380.66_beta1-g7b22cbf - Need to update this, I'm aware) rockets up to 100%. The server responses are abysmally slow, and I only get 1/10th of all the servers that should be active. I only get a few hundred show up at best.

I then used a software VPN solution and re-ran the test. The server list loads almost immediately and I get roughly 2700 servers in the list.

Am I hitting a hardware limitation on the router, as Core1 hits 100% and Core2 remains low while I do a scan. Stop the scan, cpu usage drops back down to nominal values. On the software VPN (obviously this will only create a single stream of traffic so the router doesn't need to do the heavy lifting), everything's fine.

I have DDoS disabled under WAN, so it's not that, I don't think.

Also, during a game server scan, the web ui of the router becomes unresponsive (although if I'm on the home page the CPU graph does go up, as seen attached).

I've attached a screenshot of the CPU graph, I'm just wondering if I hit a H/W limit on the number of sessions the game tries to create, or it's a software problem.

 

[Nexy]

Also, to confirm, this testing is done via Wired, not wireless. Reproducible 100% of the time. Run a server scan, 100% Core1 usage.

EDIT: Or, am I hitting a windows limit on the number of connections I can have open, since the box will be pinging hundreds of servers at the same time, and the 100% cpu usage on the router is just a coincidence?

EDIT2: Actually, I ran a speedtest.net test on my mobile to rule out Windows, during the test, I was getting 200mbps, which then plummeted, and my upload speed was far lower than it should be too. I understand that scanning for games should use some resources, but not cut down the download speed to miniscule levels on another device.

I uploaded a picture of traffic usage. In this picture, I ran a speedtest, and then ran a second speedtest while doing a game server scan right after the spike. You'll see, the traffic was pitiful, I got 1mbps down, 0.02mbps up.

I am almost certain the issue lies with the router.

 

[Nexy]

Updated to 380.67 (latest merlin build), issue persists.

 

[ColinTaylor]

Are you using a VPN client on the router? If so turn it off and try again.

 

[Nexy]

Hi Colin.

No, I don't use a VPN client, nor server (on the router). I even tried disabling QoS in case that was a likely culprit. No dice. Still kills the internet for all connected devices while the game scans for servers. I think it's a unique connections per second problem, but I don't know how to track that. Netstat from the router maybe?

 

[RMerlin]

Disable firewall packet logging if you had enabled it, or it will overload your cpu.

Sent from my Nexus 5X using Tapatalk

 

[Nexy]

RMerlin,

This was bang on the money. This fixed it, appreciate all the help folks!

I'll go back and turn QoS back on