ThreadPool.GetMaxThreads(Int32, Int32) 메서드

정의

네임스페이스:

System.Threading

어셈블리:

mscorlib.dll

동시에 활성화될 수 있는 스레드 풀에 대한 요청 수를 검색합니다. 스레드 풀 스레드를 사용할 수 있게 될 때까지 해당 수 이상의 모든 요청은 대기 상태로 유지됩니다.

public:
 static void GetMaxThreads([Runtime::InteropServices::Out] int % workerThreads, [Runtime::InteropServices::Out] int % completionPortThreads);

public static void GetMaxThreads(out int workerThreads, out int completionPortThreads);

static member GetMaxThreads : int * int -> unit

Public Shared Sub GetMaxThreads (ByRef workerThreads As Integer, ByRef completionPortThreads As Integer)

매개 변수

workerThreads

Int32

스레드 풀의 최대 작업자 스레드 수입니다.

completionPortThreads

Int32

스레드 풀의 최대 비동기 I/O 스레드 수입니다.

예제

다음 코드 예제에서는 스레드 풀에서 사용 가능한 최대 스레드 수와 최대 스레드 수를 검색하는 방법을 보여 줍니다. 두 파일에 비동기적으로 쓰는 데 사용하는 FileStream 작업 항목이 큐에 대기됩니다. 콜백 메서드는 겹치도록 시간이 초과됩니다. 작업자 스레드는 작업 항목을 처리하고 컴퓨터의 프로세서 속도와 수에 따라 하나 또는 두 개의 완료 포트 스레드가 쓰기 작업을 처리합니다.

using System;
using System.IO;
using System.Security.Permissions;
using System.Threading;

class Test
{
    static void Main()
    {
        AutoResetEvent mainEvent = new AutoResetEvent(false);
        int workerThreads;
        int portThreads;

        ThreadPool.GetMaxThreads(out workerThreads, out portThreads);
        Console.WriteLine("\nMaximum worker threads: \t{0}" +
            "\nMaximum completion port threads: {1}",
            workerThreads, portThreads);

        ThreadPool.GetAvailableThreads(out workerThreads, 
            out portThreads);
        Console.WriteLine("\nAvailable worker threads: \t{0}" +
            "\nAvailable completion port threads: {1}\n",
            workerThreads, portThreads);

        ThreadPool.QueueUserWorkItem(new 
            WaitCallback(ThreadPoolTest.WorkItemMethod), mainEvent);
           
        // Since ThreadPool threads are background threads, 
        // wait for the work item to signal before ending Main.
        mainEvent.WaitOne(5000, false);
    }
}

class ThreadPoolTest
{
    // Maintains state information to be passed to EndWriteCallback.
    // This information allows the callback to end the asynchronous
    // write operation and signal when it is finished.
    class State
    {
        public FileStream     fStream;
        public AutoResetEvent autoEvent;

        public State(FileStream fStream, AutoResetEvent autoEvent)
        {
            this.fStream   = fStream;
            this.autoEvent = autoEvent;
        }
    }

    ThreadPoolTest() {}

    public static void WorkItemMethod(object mainEvent)
    {
        Console.WriteLine("\nStarting WorkItem.\n");
        AutoResetEvent autoEvent = new AutoResetEvent(false);

        // Create some data.
        const int ArraySize  = 10000;
        const int BufferSize =  1000;
        byte[] byteArray = new Byte[ArraySize];
        new Random().NextBytes(byteArray);

        // Create two files and two State objects. 
        FileStream fileWriter1 = 
            new FileStream(@"C:\Test1@##.dat", FileMode.Create, 
            FileAccess.ReadWrite, FileShare.ReadWrite, 
            BufferSize, true);
        FileStream fileWriter2 = 
            new FileStream(@"C:\Test2@##.dat", FileMode.Create, 
            FileAccess.ReadWrite, FileShare.ReadWrite, 
            BufferSize, true);
        State stateInfo1 = new State(fileWriter1, autoEvent);
        State stateInfo2 = new State(fileWriter2, autoEvent);

        // Asynchronously write to the files.
        fileWriter1.BeginWrite(byteArray, 0, byteArray.Length, 
            new AsyncCallback(EndWriteCallback), stateInfo1);
        fileWriter2.BeginWrite(byteArray, 0, byteArray.Length, 
            new AsyncCallback(EndWriteCallback), stateInfo2);

        // Wait for the callbacks to signal.
        autoEvent.WaitOne();
        autoEvent.WaitOne();

        fileWriter1.Close();
        fileWriter2.Close();
        Console.WriteLine("\nEnding WorkItem.\n");

        // Signal Main that the work item is finished.
        ((AutoResetEvent)mainEvent).Set();
    }

    static void EndWriteCallback(IAsyncResult asyncResult)
    {
        Console.WriteLine("Starting EndWriteCallback.");

        State stateInfo = (State)asyncResult.AsyncState;
        int workerThreads;
        int portThreads;
        try
        {
            ThreadPool.GetAvailableThreads(out workerThreads, 
                out portThreads);
            Console.WriteLine("\nAvailable worker threads: \t{0}" +
                "\nAvailable completion port threads: {1}\n",
                workerThreads, portThreads);

            stateInfo.fStream.EndWrite(asyncResult);

            // Sleep so the other thread has a chance to run
            // before the current thread ends.
            Thread.Sleep(1500);
        }
        finally
        {
            // Signal that the current thread is finished.
            stateInfo.autoEvent.Set();
            Console.WriteLine("Ending EndWriteCallback.");
        }
    }
}

Imports System.IO
Imports System.Security.Permissions
Imports System.Threading

Public Class Example
    Shared Sub Main()
        Dim mainEvent As New AutoResetEvent(False)
        Dim workerThreads As Integer 
        Dim portThreads As Integer 

        ThreadPool.GetMaxThreads(workerThreads, portThreads)
        Console.WriteLine(vbCrLf & "Maximum worker threads: " & _
            vbTab & "{0}" & vbCrLf & "Maximum completion port " & _
            "threads: {1}", workerThreads, portThreads)

        ThreadPool.GetAvailableThreads(workerThreads, portThreads)
        Console.WriteLine(vbCrLf & "Available worker threads: " & _
            vbTab & "{0}" & vbCrLf & "Available completion port " & _
            "threads: {1}" & vbCrLf, workerThreads, portThreads)

        ThreadPool.QueueUserWorkItem(AddressOf _
            ThreadPoolTest.WorkItemMethod, mainEvent)
           
        ' Since ThreadPool threads are background threads, 
        ' wait for the work item to signal before ending Main.
        mainEvent.WaitOne(5000, False)
    End Sub

End Class

Public Class ThreadPoolTest

    ' Maintains state information to be passed to EndWriteCallback.
    ' This information allows the callback to end the asynchronous
    ' write operation and signal when it is finished.
    Class State
        Public fStream As FileStream
        Public autoEvent As AutoResetEvent

        Public Sub New(aFileStream As FileStream, anEvent As AutoResetEvent)
            fStream   = aFileStream
            autoEvent = anEvent
        End Sub
    End Class   
    
    Private Sub New
    End Sub

    Shared Sub WorkItemMethod(mainEvent As Object)
    
        Console.WriteLine(vbCrLf & "Starting WorkItem." & vbCrLf)
        Dim autoEvent As New AutoResetEvent(False)

        ' Create some data.
        Const ArraySize As Integer  = 10000
        Const BufferSize As Integer =  1000
        Dim byteArray As Byte() = New Byte(ArraySize){}
        Dim randomGenerator As New Random()
        randomGenerator.NextBytes(byteArray)

        ' Create two files and two State objects. 
        Dim fileWriter1 As FileStream = _
            New FileStream("C:\Test1111.dat", FileMode.Create, _
            FileAccess.ReadWrite, FileShare.ReadWrite, _
            BufferSize, True)
        Dim fileWriter2 As FileStream = _
            New FileStream("C:\Test2222.dat", FileMode.Create, _
            FileAccess.ReadWrite, FileShare.ReadWrite, _
            BufferSize, True)
        Dim stateInfo1 As New State(fileWriter1, autoEvent)
        Dim stateInfo2 As New State(fileWriter2, autoEvent)

        ' Asynchronously write to the files.
        fileWriter1.BeginWrite(byteArray, 0, byteArray.Length, _
            AddressOf EndWriteCallback, stateInfo1)
        fileWriter2.BeginWrite(byteArray, 0, byteArray.Length, _
            AddressOf EndWriteCallback, stateInfo2)

        ' Wait for the callbacks to signal.
        autoEvent.WaitOne()
        autoEvent.WaitOne()

        fileWriter1.Close()
        fileWriter2.Close()
        Console.WriteLine(vbCrLf & "Ending WorkItem." & vbCrLf)

        ' Signal Main that the work item is finished.
        DirectCast(mainEvent, AutoResetEvent).Set()
    
    End Sub

    Shared Sub EndWriteCallback(asyncResult As IAsyncResult)
        Console.WriteLine("Starting EndWriteCallback.")

        Dim stateInfo As State = _
            DirectCast(asyncResult.AsyncState, State)
        Dim workerThreads As Integer 
        Dim portThreads As Integer 
        Try
            ThreadPool.GetAvailableThreads(workerThreads, portThreads)
            Console.WriteLine(vbCrLf & "Available worker " & _
                "threads:" & vbTab & "{0}" & vbCrLf & "Available " & _
                "completion port threads: {1}" & vbCrLf, _
                workerThreads, portThreads)

            stateInfo.fStream.EndWrite(asyncResult)

            ' Sleep so the other thread has a chance to run
            ' before the current thread ends.
            Thread.Sleep(1500)
        Finally
        
            ' Signal that the current thread is finished.
            stateInfo.autoEvent.Set()
            Console.WriteLine("Ending EndWriteCallback.")
        End Try
    
    End Sub
End Class

설명

반환될 때 GetMaxThreads 지정된 workerThreads 변수에는 스레드 풀에서 허용되는 최대 작업자 스레드 수가 포함되며, 지정된 completionPortThreads 변수에는 스레드 풀에서 허용되는 최대 비동기 I/O 스레드 수가 포함됩니다.

메서드를 GetAvailableThreads 사용하여 지정된 시간에 스레드 풀의 실제 스레드 수를 확인할 수 있습니다.

이를 SetMaxThreads 사용하여 스레드 풀에서 최대 작업자 스레드 수와 비동기 I/O 스레드 수를 설정할 수 있습니다.

시스템 메모리에서 허용하는 만큼 스레드 풀 요청을 큐에 대기할 수 있습니다. 스레드 풀 스레드보다 더 많은 요청이 있는 경우 스레드 풀 스레드를 사용할 수 있을 때까지 추가 요청이 대기 상태로 유지됩니다.

추가 정보

• SetMinThreads(Int32, Int32)
• GetMinThreads(Int32, Int32)
• GetAvailableThreads(Int32, Int32)
• SetMaxThreads(Int32, Int32)