WSL2 mirrored network mode slows VSCode debugging - still not resolved

[aknuth]

• VS Code Version: 1.84.2
• OS Version: 10.0.22621.2715
• wsl Version: 2.0.9.0

Steps to Reproduce:

1. create wsl config like this
   [wsl2]
   memory=8G
   networkingMode=mirrored
2. start your WSL2 distribution (actually I took ubuntu 22.04)
3. install node.js (e.g. by using nvm - curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.5/install.sh | bash && nvm install --lts && nvm use --lts)
4. attach your Windows VSCode to a remote WSL folder and create a simple test.js file with one line of code -> console.log('test')
5. create a launch config like
   {
   "version": "0.2.0",
   "configurations": [
   {
   "type": "node",
   "request": "launch",
   "name": "test",
   "skipFiles": ["<node_internals>/**"],
   "program": "${workspaceFolder}/test.js"
   },
   ]
   }
6. create a breakpoint in test.js and start debugging test.js
   It will take about 1-2 min until the breakpoint is reached. Removing the networkingMode=mirrored from the WSL configuration and restarting the WSL distro will immediately stop at the breakpoint.

[connor4312]

/jsDebugLogs

[vscodenpa]

Please collect trace logs using the following instructions:

If you're able to, add "trace": true to your launch.json and reproduce the issue. The location of the log file on your disk will be written to the Debug Console. Share that with us.

⚠️ This log file will not contain source code, but will contain file paths. You can drop it into https://microsoft.github.io/vscode-pwa-analyzer/index.html to see what it contains. If you'd rather not share the log publicly, you can email it to [email protected]

[connor4312]

I'm not sure this is an issue in the debugger necessarily vs one in WSL, but the log might help indicate what's going wrong

[aknuth]

trace.log added - hope it helps
vscode-debugadapter-262f3b82.json.gz

[zed76r]

vscode-debugadapter-be4071cd.json.gz

[connor4312]

This appears to be an upstream issue, we have had a bevy of problems since the latest WSL update with mirrored network mode, e.g. #198285

THere are reports of similar issues outside of debugging, e.g. microsoft/WSL#10844

[meanderix]

For anyone else coming across this issue, I managed to resolve it by using the following commands (Ubuntu 24.04 with mirrored network mode):

ethtool -K eth0 tso off
ethtool -K lo tso off
ethtool -K loopback0 tso off

I think it's also related to microsoft/WSL#8171.