Very slow network speed on WSL2

[carl-berg]

Windows build number: 10.0.19041.84
Dist: Ubuntu 18.04 LTS

I just installed WSL2 on my home computer for the first time and something i notice that i don't see on my work computer is that WSL2 has dramatically lower network speed (wget or git clone tested). Speeds on WSL seem to be about 10-20 kb/s wheras windows download speed seem to be correlating to my ISP spec of 100/10 Mbps or above.

[therealkenc]

Screencap speedtest-cli as a starting point.

$ sudo apt install speedtest-cli
$ speedtest-cli
[...]

[carl-berg]

Okies, here's speedtest on windows, in the browser:

...and here's speedtest from wsl2:

[acirulis]

Same here. Especially upload speed was drastically reduced - 36.61 -> 3.85 Mbit/s

[guilhermehrcosta]

Hi, same here. My download was drastrically reduced of 200Mbit/s to 2 Mbit/s. Is there a solution?

[AndrewGaspar]

I'm hitting this issue, as well. Very frustrating.

[kennethnipper]

I'm seeing same issue. Speedtest-cli in bash:

speedtest in Windows:

[tin-liu]

Edit: After several reboots and adding the related folders as exceptions in Windows Defender as @jituanlin 's referred blog pointed out, and then tried removing the exceptions because I wanted to check which folder exception actually helped (so eventually theoretically equivalent to reboots-only, but who knows?), now in WSL Ubuntu Ver. 2 I have down = ~80 Mbit/s & up = ~4 Mbit/s. The upload is still about only 1/10 of the actual limit, but the download is up-to-standard now.

Also, the command speedtest is ~15 Mbit/s faster (download) than speedtest-cli for me.

Old comment:
Windows network faster than WSL Ubuntu Ver. 1 which faster than WSL Ubuntu Ver. 2 here:

1. Windows Ookla on Web browser
   down ~88 Mbit/s
   up ~38 Mbit/s
2. WSL Ubuntu Ver. 1 speedtest-cli
   down ~32 Mbit/s
   up ~4 Mbit/s
3. WSL Ubuntu Ver. 2 speedtest-cli
   down ~3 Mbit/s
   up ~4 Mbit/s

Cheers

[PoldarnKJ]

After follow this blog
My network/file access improve more than 5 times speed.

[rducom]

Same here, really annoying. Disabling AV (defender) doesn't helps