I'm working on a multiplayer game. The principle is simple, each of the two players sends each other periodically 512 bytes every 50 milliseconds.
The problem is that about every 20-30 seconds players stop receiving data for sometimes one but sometimes even up to 20 seconds (though, sending had not been interrupted).
At first I thought that this is caused by a slow network connection on either my side or on the side of my remote PC which I use for debugging.
But then I noticed that all network traffic on my side slows down at the same times when the game stops receiving data.
So I started ping <my-local-router> and this is what it shows me:
When the game isn't running: ... 64 bytes from 192.168.1.1: icmp_req=4520 ttl=64 time=4.89 ms 64 bytes from 192.168.1.1: icmp_req=4521 ttl=64 time=7.96 ms 64 bytes from 192.168.1.1: icmp_req=4522 ttl=64 time=10.5 ms 64 bytes from 192.168.1.1: icmp_req=4523 ttl=64 time=7.21 ms 64 bytes from 192.168.1.1: icmp_req=4524 ttl=64 time=8.10 ms 64 bytes from 192.168.1.1: icmp_req=4525 ttl=64 time=3.37 ms 64 bytes from 192.168.1.1: icmp_req=4526 ttl=64 time=5.12 ms 64 bytes from 192.168.1.1: icmp_req=4527 ttl=64 time=3.29 ms ...
When the game is running: ... 64 bytes from 192.168.1.1: icmp_req=47 ttl=64 time=6.99 ms 64 bytes from 192.168.1.1: icmp_req=48 ttl=64 time=1.69 ms 64 bytes from 192.168.1.1: icmp_req=49 ttl=64 time=2.60 ms 64 bytes from 192.168.1.1: icmp_req=50 ttl=64 time=2.88 ms 64 bytes from 192.168.1.1: icmp_req=52 ttl=64 time=9210 ms 64 bytes from 192.168.1.1: icmp_req=53 ttl=64 time=17144 ms 64 bytes from 192.168.1.1: icmp_req=54 ttl=64 time=16214 ms 64 bytes from 192.168.1.1: icmp_req=55 ttl=64 time=15372 ms 64 bytes from 192.168.1.1: icmp_req=56 ttl=64 time=14482 ms 64 bytes from 192.168.1.1: icmp_req=57 ttl=64 time=13486 ms 64 bytes from 192.168.1.1: icmp_req=58 ttl=64 time=12511 ms 64 bytes from 192.168.1.1: icmp_req=59 ttl=64 time=11546 ms 64 bytes from 192.168.1.1: icmp_req=60 ttl=64 time=10591 ms 64 bytes from 192.168.1.1: icmp_req=61 ttl=64 time=9626 ms 64 bytes from 192.168.1.1: icmp_req=62 ttl=64 time=1.34 ms 64 bytes from 192.168.1.1: icmp_req=63 ttl=64 time=3.33 ms ...
It seems that the game is causing the router to become unresponsive.
I don't have any P2P running on my local PC, but that doesn't even sound relevant since I don't experience the slowback when the game isn't running.
I'm new to UDP programming and I'm getting clueless with this, especially since the 512 bytes every 50ms seems like quite a small bandwidth to me (when I do run P2P, it easily runs 1.5MB/s).
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