GC.WaitForPendingFinalizers Méthode

Définition

Espace de noms:

System

Assembly:

System.Runtime.dll

Source:

GC.CoreCLR.cs

Suspend le thread actif jusqu'à ce que le thread traitant la file d'attente des finaliseurs ait vidé cette file d'attente.

public:
 static void WaitForPendingFinalizers();

public static void WaitForPendingFinalizers ();

static member WaitForPendingFinalizers : unit -> unit

Public Shared Sub WaitForPendingFinalizers ()

Exemples

L’exemple suivant montre comment utiliser la WaitForPendingFinalizers méthode pour suspendre le thread actuel jusqu’à la finalisation de tous les objets collectés.

using namespace System;
ref class MyFinalizeObject
{
private:

   // Make this number very large to cause the finalizer to
   // do more work.
   literal int maxIterations = 10000;
   ~MyFinalizeObject()
   {
      Console::WriteLine( "Finalizing a MyFinalizeObject" );
      
      // Do some work.
      for ( int i = 0; i < maxIterations; i++ )
      {
         
         // This method performs no operation on i, but prevents
         // the JIT compiler from optimizing away the code inside
         // the loop.
         GC::KeepAlive( i );

      }
   }

};


// You can increase this number to fill up more memory.
const int numMfos = 1000;

// You can increase this number to cause more
// post-finalization work to be done.
const int maxIterations = 100;
int main()
{
   MyFinalizeObject^ mfo = nullptr;
   
   // Create and release a large number of objects
   // that require finalization.
   for ( int j = 0; j < numMfos; j++ )
   {
      mfo = gcnew MyFinalizeObject;

   }
   
   //Release the last object created in the loop.
   mfo = nullptr;
   
   //Force garbage collection.
   GC::Collect();
   
   // Wait for all finalizers to complete before continuing.
   // Without this call to GC::WaitForPendingFinalizers,
   // the worker loop below might execute at the same time
   // as the finalizers.
   // With this call, the worker loop executes only after
   // all finalizers have been called.
   GC::WaitForPendingFinalizers();
   
   // Worker loop to perform post-finalization code.
   for ( int i = 0; i < maxIterations; i++ )
   {
      Console::WriteLine( "Doing some post-finalize work" );

   }
}

using System;

namespace WaitForPendingFinalizersExample
{
   class MyWaitForPendingFinalizersClass
   {
    // You can increase this number to fill up more memory.
    const int numMfos = 1000;
    // You can increase this number to cause more
    // post-finalization work to be done.
    const int maxIterations = 100;

    static void Main(string[] args)
    {
       MyFinalizeObject mfo = null;

       // Create and release a large number of objects
       // that require finalization.
       for(int j = 0; j < numMfos; j++)
       {
          mfo = new MyFinalizeObject();
       }

       //Release the last object created in the loop.
       mfo = null;

       //Force garbage collection.
       GC.Collect();

       // Wait for all finalizers to complete before continuing.
       // Without this call to GC.WaitForPendingFinalizers,
       // the worker loop below might execute at the same time
       // as the finalizers.
       // With this call, the worker loop executes only after
       // all finalizers have been called.
       GC.WaitForPendingFinalizers();

       // Worker loop to perform post-finalization code.
       for(int i = 0; i < maxIterations; i++)
       {
          Console.WriteLine("Doing some post-finalize work");
       }
    }
   }

   class MyFinalizeObject
   {
    // Make this number very large to cause the finalizer to
    // do more work.
    private const int maxIterations = 10000;

    ~MyFinalizeObject()
    {
       Console.WriteLine("Finalizing a MyFinalizeObject");
            
       // Do some work.
       for(int i = 0; i < maxIterations; i++)
       {
          // This method performs no operation on i, but prevents
          // the JIT compiler from optimizing away the code inside
          // the loop.
          GC.KeepAlive(i);
       }
        }
    }
}

open System

// You can increase this number to fill up more memory.
let numMfos = 1000

// You can increase this number to cause more
// post-finalization work to be done.
let maxIterations = 100

[<AllowNullLiteral>]
type MyFinalizeObject() =
    // Make this number very large to cause the finalizer todo more work.
    let maxIterations = 10000

    override _.Finalize() =
        printfn "Finalizing a MyFinalizeObject"
        
        // Do some work.
        for i = 1 to maxIterations do
            // This method performs no operation on i, but prevents
            // the JIT compiler from optimizing away the code inside
            // the loop.
            GC.KeepAlive i

let mutable mfo = null

// Create and release a large number of objects
// that require finalization.
for j = 1 to numMfos do
    mfo <- MyFinalizeObject()

//Release the last object created in the loop.
mfo <- null

//Force garbage collection.
GC.Collect()

// Wait for all finalizers to complete before continuing.
// Without this call to GC.WaitForPendingFinalizers,
// the worker loop below might execute at the same time
// as the finalizers.
// With this call, the worker loop executes only after
// all finalizers have been called.
GC.WaitForPendingFinalizers()

// Worker loop to perform post-finalization code.
for _ = 1 to maxIterations do
    printfn "Doing some post-finalize work"

Namespace WaitForPendingFinalizersExample
   Class MyWaitForPendingFinalizersClass
  
    ' You can increase this number to fill up more memory.
      Private Const numMfos As Integer = 1000
      ' You can increase this number to cause more
      ' post-finalization work to be done.
      Private Const maxIterations As Integer = 100
     
      Overloads Shared Sub Main()
         Dim mfo As MyFinalizeObject = Nothing
      
         ' Create and release a large number of objects
         ' that require finalization.
         Dim j As Integer
         For j = 0 To numMfos - 1
            mfo = New MyFinalizeObject()
         Next j
      
         'Release the last object created in the loop.
         mfo = Nothing
      
         'Force garbage collection.
         GC.Collect()
      
         ' Wait for all finalizers to complete before continuing.
         ' Without this call to GC.WaitForPendingFinalizers, 
         ' the worker loop below might execute at the same time 
         ' as the finalizers.
         ' With this call, the worker loop executes only after
         ' all finalizers have been called.
         GC.WaitForPendingFinalizers()
      
         ' Worker loop to perform post-finalization code.
         Dim i As Integer
         For i = 0 To maxIterations - 1
            Console.WriteLine("Doing some post-finalize work")
         Next i
      End Sub
   End Class


   Class MyFinalizeObject
      ' Make this number very large to cause the finalizer to
      ' do more work.
      Private maxIterations As Integer = 10000
      
      Protected Overrides Sub Finalize()
         Console.WriteLine("Finalizing a MyFinalizeObject")
      
         ' Do some work.
         Dim i As Integer
         For i = 0 To maxIterations - 1
            ' This method performs no operation on i, but prevents 
            ' the JIT compiler from optimizing away the code inside 
            ' the loop.
            GC.KeepAlive(i)
         Next i
         MyBase.Finalize()
      End Sub
   End Class
End Namespace

Remarques

Lorsque le récupérateur de mémoire trouve des objets qui peuvent être récupérés, il vérifie chaque objet pour déterminer les exigences de finalisation de l’objet. Si un objet implémente un finaliseur et n’a pas désactivé la finalisation en appelant SuppressFinalize, l’objet est placé dans une liste d’objets marqués comme prêts pour la finalisation. Le récupérateur de mémoire appelle les Finalize méthodes pour les objets de cette liste et supprime les entrées de la liste. Cette méthode se bloque jusqu’à ce que tous les finaliseurs aient été exécutés jusqu’à la fin.

Le thread sur lequel les finaliseurs sont exécutés n’est pas spécifié, il n’est donc pas garanti que cette méthode se termine. Toutefois, ce thread peut être interrompu par un autre thread pendant que la WaitForPendingFinalizers méthode est en cours. Par exemple, vous pouvez démarrer un autre thread qui attend un certain temps, puis l’interrompre si ce thread est toujours suspendu.