How to use max bandwidth for prolonged time?

EnthusiastXYZ

Limp Gawd
Joined
Jun 26, 2020
Messages
221
How to max out my bandwidth for a prolonged time? Speedtest.net only performs a short test. I want to be downloading/uploading (or using a lot of bandwidth) for a prolonged time.

I thought that a very popular torrent download would do the trick, but which one? It has to be lawful/legal, even though I use VPN. It can be something other than torrent, but has to max out at least download speed.
 
You most likely will have to do this over multiple connections. If you are using speetest.net and not single.speedtest.net, you're already testing with multiple connections.
I have nothing off the top of my head that concrete but...

You can find various Linux distributions.
Windows ISOs directly from Microsoft.
Get steam and buy a game like some call of war duty halo?

Also, what are you trying to accomplish?
 
How much bandwidth are you trying to max out?
And for how long? A gigabit connection will (theoretically) download 7.5 GB/min, 450 GB/hr, 10.8 TB/day. You'll need to play with the formula: bandwidth * time = file size.
 
Wow a new low .... hmm copy some arbitrary number of GB to an AWS bucket. FMD! That was hard.
 
My router, Unifi Dream Machine (UDM), has no problem handling 500Mbps connection at full 500Mbps (for download) that my cable ISP advertises. To test bandwidth/throughput, I make sure to connect/use only one wired client (my PC), use Ubiquiti default settings, but disable IDS/IPS, and not use a VPN. At full ISP-advertised download speed of 500Mbps and 500Mbps throughput test result from speedtest.net, WAN Ethernet port shows 0 overruns and 0 errors when I view "ifconfig" stats over SSH. All seems fine.

After a while, my connection slows down by either exactly 250Mbps or by exactly 75Mbps. When that happens, "ifconfig" stats show overruns in 1000's and errors in 100's. Overruns and errors from overruns indicate that WAN Ethernet port is reeving data at throughput higher than it can process. Upload speed is 100Mbps and stays the same all the time.

I can restore speed back to 500Mbps by flushing caches using the following commands:
Code:
arp -d <Local IP>
arp -d <WAN IP>
ip -s -s neigh flush all
ip route flush cache
killall -HUP dnsmasq

I am trying to troubleshoot this issue, but not sure how... My logic is that if cleaning ARP, DNS, and route caches restores throughput, then caching is the problem, but I don't know how to find out for sure... I try many SysCTL kernel tweaks related to cache to see if that improves anything, but so far it doesn't. I think having stats and logs from prolonged high-throughput use can point at something, but I am not sure... I need to catch the moment at which speed drops to see what router logs show for that moment.

Can a port mirroring device on ISP's local switch result in such overruns? I don't think so... SPAN can reduce bandwidth, but overruns are probably caused by router not being able to handle 500Mbps throughput after a while and yet UDM stats show that router CPU load stays at about 10-20% and has plenty of unused RAM.
 
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My router, Unifi Dream Machine (UDM), has no problem handling 500Mbps connection at full 500Mbps (for download) that my cable ISP advertises. To test bandwidth/throughput, I make sure to connect/use only one wired client (my PC), use Ubiquiti default settings, but disable IDS/IPS, and not use a VPN. At full ISP-advertised download speed of 500Mbps and 500Mbps throughput test result from speedtest.net, WAN Ethernet port shows 0 overruns and 0 errors when I view "ifconfig" stats over SSH. All seems fine.

After a while, my connection slows down by either exactly 250Mbps or by exactly 75Mbps. When that happens, "ifconfig" stats show overruns in 1000's and errors in 100's. Overruns and errors from overruns indicate that WAN Ethernet port is reeving data at throughput higher than it can process. Upload speed is 100Mbps and stays the same all the time.

I can restore speed back to 500Mbps by flushing caches using the following commands:
Code:
arp -d <Local IP>
arp -d <WAN IP>
ip -s -s neigh flush all
ip route flush cache
killall -HUP dnsmasq

I am trying to troubleshoot this issue, but not sure how... My logic is that if cleaning ARP, DNS, and route caches restores throughput, then caching is the problem, but I don't know how to find out for sure... I try many SysCTL kernel tweaks related to cache to see if that improves anything, but so far it doesn't. I think having stats and logs from prolonged high-throughput use can point at something, but I am not sure... I need to catch the moment at which speed drops to see what router logs show for that moment.

Can a port mirroring device on ISP's local switch result in such overruns? I don't think so... SPAN can reduce bandwidth, but overruns are probably caused by router not being able to handle 500Mbps throughput after a while and yet UDM stats show that router CPU load stays at about 10-20% and has plenty of unused RAM.
Honestly, the first thing I would do is change the cable feeding the wan port and see if that solves the problem. Marginal cable will show these types of issues.

As far as a sustained download--to reach these types of speeds, I would do a 'simulated isp' and take a system and run a dhcp server and iperf server on it. Then connect it to the wan of the unifi and run your test using the iperf client--you should be able to saturate the bandwidth well above 500Mbs using this and for as long as you'd like. (y)
 
Online Packet loss tests can help diagnose too
If packet loss is the issue between his router and the Internet itself, I'm not sure if an online test would pick that up since the packets would never 'make it out the door'. But it would be interesting to see such test results--my favorite test is packetlosstest.com because it can even show 'late' packets. I'll typically use the '1080p' setting.
 
iperf or iperf3, use a public iperf (or iperf3) server and run the iperf (or iperf3) client on something in your house. Can run it for as long as you want.
 
You can use torrent and download multiple linux ISO. CentOS, Ubuntu, Debian, Gentoo.
 
Internet Download Manager consistently maxes or nearly maxes my gigabit line.
 
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