nanosleep sleeps less than request time

[Rob2309]

Windows Version

Microsoft Windows [Version 10.0.26200.7171]

WSL Version

WSL-Version: 2.6.1.0

Are you using WSL 1 or WSL 2?

• [x] WSL 2
• [ ] WSL 1

Kernel Version

6.6.87.2-microsoft-standard-WSL2

Distro Version

Ubuntu 24.04

Other Software

No response

Repro Steps

Run the following rust program:

use std::{thread::sleep, time::Duration};

use chrono::Utc;

fn main() {
    loop {
        let now = Utc::now();
        println!("Then: {now:?}");

        sleep(Duration::from_secs(10));

        let now = Utc::now();
        println!("Now: {now:?}");

        println!();
    }
}

Expected Behavior

nanosleep should sleep at least the amount specified.

Actual Behavior

This simple rust program regularly prints sleep times less than 10 seconds, which should be impossible, according to the rust docs and the documentation of the underlying nanosleep syscall.

Then: 2025-11-28T17:43:48.713270129Z
Now: 2025-11-28T17:43:58.715972419Z

Then: 2025-11-28T17:43:58.716082411Z
Now: 2025-11-28T17:44:07.138078919Z   <<< less than 10s

Then: 2025-11-28T17:44:07.138195931Z
Now: 2025-11-28T17:44:17.147807293Z

This breaks programs like code tunnel, because it simply sends requests too fast:

[2025-11-28 17:40:06] trace refresh poll failed, retrying: Error getting authorization: authorization_pending The authorization request is still pending.
[2025-11-28 17:40:11] trace refresh poll failed, slowing down
[2025-11-28 17:40:20] trace refresh poll failed, slowing down

The slowing down messages only occur when sending requests faster than the interval specified by the server. I traced this problem down to a sleep call in vscode.

This problem happens on my laptop, but not on my desktop. However, it seems to be unrelated to hibernation, as it also happens after a full system restart or wsl --shutdown.

Diagnostic Logs

No response

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This issue has been automatically closed since it has not had any author activity for the past 7 days. If you're still experiencing this issue please re-file it as a new issue.

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