Question Regular long lag spikes - how to debug?

[Nakroma]

Hello,

I'm currently experiencing pretty regular lag spikes, I'd say roughly every hour, sometimes a bit more often, sometimes a little less often. They last from a couple of seconds to about a minute. During them almost all of the internet is completely gone - it's a bit weird, for example an online stream or online video game will stop having connection, but voice chat or the chat of the stream will be a bit degraded but keep going .
I've only noticed them now because I've been playing more online games recently, but I don't know since when they occur, a year or so ago I definitely didn't have this problem.

The only thing that has changed since then, is that I've added a NAS to the network, however I took that offline for testing and the lag spikes still occured. Obviously tried router restarting but that doesn't help either. It also occurs on the entire network and not just my PC as far as I can tell, I've tested it with another PC and during a lag spike it was also noticable on there.

Some more details:

• I have 500 Mbit/s download, 30 Mbit/s upload from PYUR (Germany) cable (DOCSIS)
• Router is a FRITZ!Box 6660 Cable
• Connected to the router via ethernet are 3 devices (2 PCs and the NAS), connected via WLAN are roughly 7 (2 phones, 2 laptops, 1 tablet, 1-2 smart TV related devices) (this number obv changes sometimes depending on whats on and whats not but that's the gist of it)

I'm asking here because I know very little about networking and don't even know where to start debugging this. The fritzbox doesn't show any obvious errors or unusual usage during these lag spikes, I've tried running Wireshark and nothing looked unusual (altough I can barely read it to begin with).

Thanks for your help in advance!

 

[helpstar]

did you check while connected by ethernet or wlan?
did you check the cable frequencies in the Fritzbox, while the lag is happening? any lost or all there?
check with your local ISP PYUR, if they can have a look at the connection speed or time outs. Cable is a shared medium, so might be your neighbors downloading/uploading at the same time and the bandwidth is not enough for all of you.
Might be the fritzbox having problems

 

[Ralston18]

Also check your system's logs: Reliability History/Monitor and Event Viewer.

Either one or both tools may be capturing some error code, warning, or even an informational event just before or at the spikes.

Also look in Task Manager > Startup for any unknown or unexpected apps being launched at startup.

Another place to look is Task Scheduler. There may some trigger in place that launches some app to attempt a backup, update, or simply just "phone home".

Lastly you can use Process Explorer (Microsoft, free) to observe system performance. If the lags are regular start watching beforehand .

Objective simply being to discover what the system is doing or trying to do at the time of the lags.

FYI:

https://learn.microsoft.com/en-us/sysinternals/downloads/process-explorer

Take your time, be methodical, watch carefully. No need to rush.
\
\

 

[bill001g]

If you used wireshark that is the hard way to look at problems like this. If you work at it you can see the exactly latency for any tcp session packet by packets.

You can more simply see this in the network tab of the resource monitor. The problem is games do not use TCP so you can't see the delays as easily.

In any case the main way to test latency is simple ping commands.

First do tracert 8.8.8.8. This will not show the problem unless you are extremely luck it is mostly to get the IP in the path.

Open at least 3 cmd windows and let constant ping run to the IP in hop 1 (your router), hop 2 ( the first ISP router for most people), and the final ip of 8.8.8.8 or maybe the game server if you can get it.

In general issues with ping to hop 1 indicates a issue with your pc and rarely the router. Issues in hop 2 indicate a issue with the connection coming to your house. Issues past there get tricky to get fixed even if you find them. It could be a issue with connectivity between ISP which are not your ISP.