Slow wired upload speed vs Linux on same hardware

Question

Intel® Ethernet Controller X550-AT2, 10G network interface on ASRock Rack ROMED8-2T with AMD EPYC 7232P processor.
Windows 10 Pro for Workstations, 2004.
Latest Windows updates and Intel drivers installed as of 09/09/2020.

This machine is a dual boot, the above Windows version, and Ubuntu 20.04.
When doing a speed test, I get good performance from Ubuntu, but very poor uploads from Windows. This is on the same machine, the exact same hardware.

The WAN link is 1000Mbps down, 50Mbps up.

This is the Windows speedtest result:

This is the Ubuntu speedtest result:

I have tried to tweak the adapter's advanced driver settings in Windows, such as disabling LSO, etc. No luck, performance remains poor.

I've also noticed it on another PC running Windows 10 Pro, and a laptop running Windows 10 Pro for Workstations, both give the same poor upload performance. Whereas my other Ubuntu 20.04 Server machine, and also my phone connected via Wi-Fi, is getting good upload speeds.

I have even taken the Windows laptop and plugged it straight into my incoming WAN connection (bypassing router), and it still gets poor upload speeds.

Incidentally, when the speed test is running, I can see that the upload looks bursty on Windows, like it is only getting chunks of data here and there, while in Linux and on Android it looks the same as the download, the graph is drawn at a consistent high rate and with consistent high values.

Answer 1

I still haven't Figured out the problem,but it seems that my upload is fine at most of the tests and the problems seems to be focused at RTMP that twitch, youtube and other streaming services/tests uses... is there any setting/registry change or something i can try to make those to not be throttled by windows 10?

Answer 2

Which type is your internet connection?
Mine is 5G, but I am unsure if the problem is related to that. But I still just don't understand, why only some Win 10 users do have that upload problems at some websites...

Answer 3

Has anyone figured out what might be causing this? I've been having this issue since at least January 2021 on my entire fleet of Windows devices.

OS affected for me:

• Windows 10 2004
• Windows 10 20H2
• Windows 2016
• Windows 2019

All devices are fully updated, firmware included.

I've tried every suggestion in this thread but I can't get my 2Gbit link past 70Mbps on Windows. Distance is a factor, as I can get 400Mbps to my local telco (which isn't my IPS). Going past a few hundred kilometers it drops to 70Mbps. The initial burst goes to 200, but drops quickly.

I've tweaked:

• Limit reservable bandwidth
• AV
• Safe mode boot
• Domain and non-domain computers
• autotuning
• Interrupt Moderation
• Receive Side Scaling
• TCP Congestion Control

I've tried the following hardware:

• Dell Optiplex 7040
• HP Elitebook 840 G5
• HPE ProLiant DL380 Gen10
• HPE ProLiant DL360 Gen10

These OS' are fine:

• ChromeOS
• Android
• MacOS
• iOS
• Linux (CentOS, HyperV)

Answer 4

I'm surprised Microsoft are unable to fix this problem. If I use the app https://www.speedtest.net/apps/windows or the cli https://www.speedtest.net/apps/cli the upload speeds over seas are all fast and good. But if I use any web browser in windows going to the speedtest.net website, the upload speed on overseas servers is just slow. This is a known problem with windows.

https://www.geekzone.co.nz/forums.asp?forumid=190&topicid=275899

Please Microsoft developers fix this issue. This problem or bug has been around for a very long time.

Answer 5

I've found a solution for me, maybe it works for somebody here. Thanks for all your contributions, I tried everything that was posted here so far, but something else helped me.

I've been for a few days trying and at some point gave up. I even updated motherboard BIOS and VBIOS. I have also tried older drivers for my network card (Killer). However, I have stumbled upon a windows service "Killer Dynamic Bandwith Optimization" and some other Killer related services. They may have been installed and half-uninstalled in the past. Just killing the all the Killer related Windows Services with Task Manager helped. They were 4 in total. This did the job for me.

If it works for you, you can edit the services to they don't start up again after reboot, because on my case there was no way to uninstall them.

I hope this helps somebody in the future.

p.s.: one thing that indicated my computer was fine was that a Linux running on a VM on the Windows machine could download at very high speeds, but Windows (the host) would be capped at around 1.5mb/s.