Hi,

I'm trying to implement the Producer-Consumer-Problem in C#.
Below is my code. The problem is, that the buffer always contains only one
element...it seems
that the Thread.Sleep() in the producer and in the consumers make the whole
app sleep
instead of only making the current thread sleep.
Maybe someone can help?

using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;
namespace ErzVerbr
{
class Program
{
private const int MAX_ELEMENTE = 100;
private const int MAX_VERBRAUCHER = 2;
private static int anzElemente = 0;
private static Stack<int> puffer = new Stack<int>(MAX_ELEMENTE);
private static Object elementeVorhanden = "";
private static Object platzFrei = "";
static void Main(string[] args)
{
puffer.Clear();
Thread erz = new Thread(new ThreadStart(erzeuge));
erz.Name = "Erzeuger";
erz.Start();
Thread[] verbr = new Thread[MAX_VERBRAUCHER];
for (int i = 0; i < MAX_VERBRAUCHER; i++)
{
verbr[i] = new Thread(new ThreadStart(verbrauche));
verbr[i].Name = "Verbraucher " + (i + 1);
verbr[i].Start();
}
Console.ReadKey();
}
static public void erzeuge()
{
while (true)
{
lock (elementeVorhanden)
{
if (anzElemente == MAX_ELEMENTE)
{
System.Console.WriteLine("Warte auf Platz...");
Monitor.Wait(platzFrei);
System.Console.WriteLine("Platz verfgbar!");
}
Random rand = new Random();
int element = rand.Next(10, 20);
puffer.Push(element);
Console.WriteLine("Element erzeugt: " +
element + ", Puffer belegt: " +
(anzElemente + 1));
anzElemente++;
Monitor.PulseAll(elementeVorhanden);
Console.WriteLine("Sleep: " + Thread.CurrentThread.Name);
Thread.Sleep(rand.Next(10, 50));
}
}
}
static public void verbrauche()
{
while (true)
{
lock (platzFrei)
{
if (anzElemente == 0)
{
System.Console.WriteLine("Warte auf Elemente...");
Monitor.Wait(elementeVorhanden);
System.Console.WriteLine("Elemente vorhanden!");
}
int element = puffer.Pop();
anzElemente--;
Console.WriteLine("Verbraucht: " + element);
Random rand = new Random();
Monitor.PulseAll(platzFrei);
Console.WriteLine("Sleep: " + Thread.CurrentThread.Name);
Thread.Sleep(rand.Next(2000, 5000));
}
}
}
}
}
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;
namespace ErzVerbr
{
class Program
{
private const int MAX_ELEMENTE = 100;
private const int MAX_VERBRAUCHER = 2;
private static int anzElemente = 0;
private static Stack<int> puffer = new Stack<int>(MAX_ELEMENTE);
private static Object elementeVorhanden = "";
private static Object platzFrei = "";
static void Main(string[] args)
{
puffer.Clear();
Thread erz = new Thread(new ThreadStart(erzeuge));
erz.Name = "Erzeuger";
erz.Start();
Thread[] verbr = new Thread[MAX_VERBRAUCHER];
for (int i = 0; i < MAX_VERBRAUCHER; i++)
{
verbr[i] = new Thread(new ThreadStart(verbrauche));
verbr[i].Name = "Verbraucher " + (i + 1);
verbr[i].Start();
}
Console.ReadKey();
}
static public void erzeuge()
{
while (true)
{
lock (elementeVorhanden)
{
if (anzElemente == MAX_ELEMENTE)
{
System.Console.WriteLine("Warte auf Platz...");
Monitor.Wait(platzFrei);
System.Console.WriteLine("Platz verfgbar!");
}
Random rand = new Random();
int element = rand.Next(10, 20);
puffer.Push(element);
Console.WriteLine("Element erzeugt: " +
element + ", Puffer belegt: " +
(anzElemente + 1));
anzElemente++;
Monitor.PulseAll(elementeVorhanden);
Console.WriteLine("Sleep: " + Thread.CurrentThread.Name);
Thread.Sleep(rand.Next(10, 50));
}
}
}
static public void verbrauche()
{
while (true)
{
lock (platzFrei)
{
if (anzElemente == 0)
{
System.Console.WriteLine("Warte auf Elemente...");
Monitor.Wait(elementeVorhanden);
System.Console.WriteLine("Elemente vorhanden!");
}
int element = puffer.Pop();
anzElemente--;
Console.WriteLine("Verbraucht: " + element);
Random rand = new Random();
Monitor.PulseAll(platzFrei);
Console.WriteLine("Sleep: " + Thread.CurrentThread.Name);
Thread.Sleep(rand.Next(2000, 5000));
}
}
}
}
}

Rene Ruppert wrote:
You're sleeping while still holding the lock, so anything else waiting
to acquire the lock will have to wait until you've finished sleeping.

See http://www.pobox.com/~skeet/csharp/threads/deadlocks.shtml (about
half way down) for a sample producer/consumer queue.

Jon

Argl... thanks. That's it.

René

newbie: GetType or typeof?
Effective strategy for using VSS in a development team?
How to Anonymous IP address in C#
string dictionary and memory issue.
Getting Event of Lock Windows OS
Why won't you give me your scrollbars?! I hate you, TreeView!
file uploading in windows application in .net
Desing problem
C++ class in DLL to be imported to C#
How select from 2 ADO.NET DataTables?