Sleep

This VB.NET Subroutine causes a program to suspend operation. It receives 1 integer parameter—the number of milliseconds to pause the program.

CPU notes

No CPU time is used by Sleep. The program simply ceases to operate. For CPU usage, consider SpinWait, which causes a delay by wasting processor cycles.

First example

Here we invoke the Sleep Sub on the Thread type. Please note how the Imports System.Threading line is included at the top of the program.

Info Sleep 0 pauses the program for zero milliseconds. Sleep 5000 pauses for five seconds. Sleep 1000 pauses for one second.

Here We invoke SpinWait(). This subroutine results in a lot of CPU usage based on the large integer passed to it.

Imports System.Threading

Module Module1

    Sub Main()
        ' Create a Stopwatch and sleep for zero milliseconds.
        Dim stopwatch As Stopwatch = stopwatch.StartNew
        Thread.Sleep(0)
        stopwatch.Stop()

        ' Write the current time.
        Console.WriteLine(stopwatch.ElapsedMilliseconds)
        Console.WriteLine(DateTime.Now.ToLongTimeString)

        ' Start a new Stopwatch.
        stopwatch = stopwatch.StartNew
        Thread.Sleep(5000)
        stopwatch.Stop()
        Console.WriteLine(stopwatch.ElapsedMilliseconds)
        Console.WriteLine(DateTime.Now.ToLongTimeString)

        ' Start a new Stopwatch.
        stopwatch = stopwatch.StartNew
        Thread.Sleep(1000)
        stopwatch.Stop()
        Console.WriteLine(stopwatch.ElapsedMilliseconds)

        ' Start a new Stopwatch and use SpinWait.
        stopwatch = stopwatch.StartNew
        Thread.SpinWait(1000000000)
        stopwatch.Stop()
        Console.WriteLine(stopwatch.ElapsedMilliseconds)
    End Sub

End Module0
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`Namespace`

To use Thread.Sleep or Thread.SpinWait, import the System.Threading namespace. These methods are part of Threading, as they are more useful when threads are involved.

A summary

The Thread.Sleep method receives an integer indicating the number of milliseconds you want the program execution to pause.

Summary, continued

The Thread.SpinWait method receives an integer indicating the amount of work to do. This results in 100% CPU usage.