Scheduled tasks stop working after 2023.04.14 1:41:36 UTC

[ugurdal]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

I've blazor wasm app that i need to run scheduled task periodically in the background. I'm triggering new Task after first render of MainLayout's OnAfterRender method. Lets say this task will print out current date every 1 second to browser console. Exactly at 2023.04.14 1:41.36 PM UTC task stops without any exception. I am able to reproduce the same error by changing the Date and time settings on my Windows 11 device. So far i've tried while loop, periodic timer, System.Threading.Timer, System.Timers.Timer or another approach that i found at stack overflow, but all of them stops working at exactly same time.

We have customers who use this app and are in different time zones. This task stopped working on all of them at the same time.

By the way this approach is working almost three years without any issues. We couldn't find any solution to this problem and we don't know when or will its going to happen in the future.

sample repo: https://github.com/ugurdal/BlazorWasmBackgroundTaskDemo

Expected Behavior

Loops will work without any issue

Steps To Reproduce

1. create new blazor wasm project via dotnet new blazorwasm -n MyBlazorApp
2. add following lines to MainLayout.Razor ( you can try while loop or periodic timer. they will both behave the same )

protected override void OnAfterRender(bool firstRender)
{
 if (firstRender)
 {
 _ = Task.Run(async () =>
 {
 while (true) 
 {
 await Task.Delay(1 * 1000);
 Console.WriteLine("ping-timer utc {0}", DateTime.UtcNow.ToUniversalTime());
 }

 // var timer = new PeriodicTimer(TimeSpan.FromSeconds(1));
 // while (await timer.WaitForNextTickAsync())
 // {
 // Console.WriteLine("ping-timer utc {0}", DateTime.UtcNow.ToUniversalTime());
 // }
 });
 }

 base.OnAfterRender(firstRender);
}

3. set the date time to 2023.04.14 and a few seconds before 1:41:36 PM UTC ( give app a couple second to start, e.g 1:41.20 )
4. start application via dotnet watch run, and new browser tab will open
5. app will print out current date to browser console
6. exactly at 1:41:36 UTC you'll see that nothing prints out to console

this screenshot was taken from the Microsoft Edge console

Exceptions (if any)

No response

.NET Version

7.0.203

Anything else?

No response

Tagging subscribers to 'arch-wasm': @lewing
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

I've blazor wasm app that i need to run scheduled task periodically in the background. I'm triggering new Task after first render of MainLayout's OnAfterRender method. Lets say this task will print out current date every 1 second. Exactly at 2023.04.14 1:41.36 PM UTC task stops without any exception. I am able to reproduce the same error by changing the Date and time settings on my Windows 11 device. So far i've tried while loop, periodic timer, System.Threading.Timer, System.Timers.Timer or another approach that i found at stack overflow, but all of them stops working at exactly same time.

We have customers who use this app and are in different time zones. This task stopped working on all of them at the same time.

By the way this approach is working almost three years without any issues. We couldn't find any solution to this problem and we don't know when or will its going to happen in the future.

sample repo: https://github.com/ugurdal/BlazorWasmBackgroundTaskDemo

Expected Behavior

Loops will work without any issue

Steps To Reproduce

1. create new blazor wasm project via dotnet new blazorwasm -n MyBlazorApp
2. add following lines to MainLayout.Razor ( you can try while loop or periodic timer. they will both behave the same )

protected override void OnAfterRender(bool firstRender)
{
 if (firstRender)
 {
 _ = Task.Run(async () =>
 {
 while (true) 
 {
 await Task.Delay(1 * 1000);
 Console.WriteLine("ping-timer utc {0}", DateTime.UtcNow.ToUniversalTime());
 }

 // var timer = new PeriodicTimer(TimeSpan.FromSeconds(1));
 // while (await timer.WaitForNextTickAsync())
 // {
 // Console.WriteLine("ping-timer utc {0}", DateTime.UtcNow.ToUniversalTime());
 // }
 });
 }

 base.OnAfterRender(firstRender);
}

3. set the date time to 2023.04.14 and a few seconds before 1:41:36 PM UTC ( give app a couple second to start, e.g 1:41.20 )
4. start application via dotnet watch run, and new browser tab will open
5. app will print out current date
6. exactly at 1:41:36 UTC you'll see that nothing prints out to console

this is my console

Exceptions (if any)

No response

.NET Version

7.0.203

Anything else?

No response

Author:	ugurdal
Assignees:	-
Labels:	arch-wasm
Milestone:	-

[kg]

This is likely because new Date().valueOf() | 0 wrapped around from positive to negative near this point in time:

> Date.parse("4/14/2023 1:40:00 PM UTC").valueOf() | 0
2147387264
> Date.parse("4/15/2023 1:40:00 PM UTC").valueOf() | 0
-2061180032 

[ugurdal]

To be more precise, at exactly 1:41:36:384 PM UTC, the time is wrapped from positive to negative.

Date.parse("4/14/2023 1:41:36:383 PM UTC").valueOf() | 0
2147483647
Date.parse("4/14/2023 1:41:36:384 PM UTC").valueOf() | 0
-2147483648

I guess this issue will happen again on 6/03/2023 6:44:23 AM UTC. He is my new test; I've updated the Windows time and started the application again.

Console output stopped at 6:44:23 AM UTC

[kg]

Now that I'm attempting to reproduce this in my Linux environment, I can't reproduce it. What is your system time zone?