VB.Net Tutorial/Thread/ThreadPool

Get Available Threads in a ThreadPool and Get Max Threads in a ThreadPool

Imports System.Threading
public class Test
   public Shared Sub Main
               Dim msg As String : Dim i As Integer
               Dim job As New MyJob()
               For i = 1 To 5
                       ThreadPool.QueueUserWorkItem(New WaitCallback(AddressOf job.MyTask), i)
               Next
               Thread.Sleep(2000)
   End Sub
End class

Public Class MyJob
       Private Msg As String
       Dim availWorker As Integer = 0 : Dim maxWorker As Integer = 0
       Dim availCPT As Integer = 0 : Dim maxCPT As Integer = 0
       
       Public Sub MyTask(ByVal ThreadStateData As Object)
               Console.WriteLine("Performing Task. Data Passed: " & ThreadStateData)
               ThreadPool.GetAvailableThreads(availWorker, availCPT)
               ThreadPool.GetMaxThreads(maxWorker, maxCPT)
               Console.WriteLine("--Available Worker Threads: " & availWorker.ToString())
               Console.WriteLine("--Maximum Worker Threads: " & maxWorker.ToString())
               Console.WriteLine("--Available Completion Port Threads: " & availCPT.ToString())
               Console.WriteLine("--Maximum Completion Port Threads: " & maxCPT)
       End Sub
End Class

Performing Task. Data Passed: 1
--Available Worker Threads: 24
--Maximum Worker Threads: 25
--Available Completion Port Threads: 1000
--Maximum Completion Port Threads: 1000
Performing Task. Data Passed: 2
--Available Worker Threads: 24
--Maximum Worker Threads: 25
--Available Completion Port Threads: 1000
--Maximum Completion Port Threads: 1000
Performing Task. Data Passed: 3
--Available Worker Threads: 24
--Maximum Worker Threads: 25
--Available Completion Port Threads: 1000
--Maximum Completion Port Threads: 1000
Performing Task. Data Passed: 4
--Available Worker Threads: 24
--Maximum Worker Threads: 25
--Available Completion Port Threads: 1000
--Maximum Completion Port Threads: 1000
Performing Task. Data Passed: 5
--Available Worker Threads: 24
--Maximum Worker Threads: 25
--Available Completion Port Threads: 1000
--Maximum Completion Port Threads: 1000

Thread Pool

Imports System.Threading
Module Module1
    Sub TaskA(ByVal state As Object)
        Dim I As Integer
        For I = 0 To 250
            System.Console.Write("A")
        Next
        Thread.Sleep(3000)
        CType(state, AutoResetEvent).Set()
    End Sub
    Sub TaskB(ByVal state As Object)
        Dim I As Integer
        For I = 0 To 250
            System.Console.Write("B")
        Next
        Thread.Sleep(3000)
        CType(state, AutoResetEvent).Set()
    End Sub
    Sub TaskC(ByVal state As Object)
        Dim I As Integer
        For I = 0 To 250
            System.Console.Write("C")
        Next
        Thread.Sleep(3000)
        CType(state, AutoResetEvent).Set()
    End Sub
    Sub Main()
        Dim AIsDone As New AutoResetEvent(False)
        Dim BIsDone As New AutoResetEvent(False)
        Dim CIsDone As New AutoResetEvent(False)
        ThreadPool.QueueUserWorkItem(New WaitCallback(AddressOf TaskA), AIsDone)
        ThreadPool.QueueUserWorkItem(New WaitCallback(AddressOf TaskB), BIsDone)
        ThreadPool.QueueUserWorkItem(New WaitCallback(AddressOf TaskC), CIsDone)
        Dim ThreadCount, ThreadPorts As Integer
        ThreadPool.GetAvailableThreads(ThreadCount, ThreadPorts)
        Console.WriteLine("Thread pool size {0}", ThreadCount)
        Console.WriteLine("Waiting for asynchronous threads to complete.")
        AIsDone.WaitOne()
        Console.WriteLine("A is done")
        BIsDone.WaitOne()
        Console.WriteLine("B is done")
        CIsDone.WaitOne()
        Console.WriteLine("C is done")
    End Sub
End Module

Thread pool size 25
Waiting for asynchronous threads to complete.
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
BBCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCA is done
B is done
C is done