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POApplication hangs using PLINQ AsParallel(). No problems with LINQ
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  1. POApplication hangs using PLINQ AsParallel(). No problems with LINQ
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    copied!<p>I'm new to LINQ and PLINQ, and I'm building a project to test them.</p> <p>Stub:</p> <pre><code>class Stub { private Boolean mytf; public Stub() { Random generator = new Random(); if (generator.NextDouble() &lt; 0.5) { mytf = false; } else mytf = true; } public Boolean tf { get { return mytf; } } } </code></pre> <p>StubCollection:</p> <pre><code>class StubCollection : IEnumerable { Stub[] stubs; public StubCollection(int n) { stubs = new Stub[n]; for (int i = 0; i &lt; n; i++) { stubs[i] = new Stub(); } } IEnumerator IEnumerable.GetEnumerator() { return new StubIterator(this); } public class StubIterator : IEnumerator { private StubCollection sc; private int index = -1; public StubIterator(StubCollection _sc) { sc = _sc; } public bool MoveNext() { index++; if (index &lt; sc.stubs.Length) { return true; } else { index = -1; return false; } } public object Current { get { if (index &lt;= -1) { throw new InvalidOperationException(); } return sc.stubs[index]; } } public void Reset() { index = -1; } } } </code></pre> <p>then I have some methods to iterate the stubcollection and count how many stubs have the boolean set to true:</p> <p>foreach:</p> <pre><code>Stopwatch sw = new Stopwatch(); Int32 n = 0; sw.Start(); foreach (Stub s in sc) if (s.tf) n++; sw.Stop(); MessageBox.Show("n:" + n.ToString() + " timer:" + sw.ElapsedMilliseconds.ToString()); </code></pre> <p>it works</p> <p>linq:</p> <pre><code>Stopwatch sw = new Stopwatch(); Int32 n = 0; sw.Start(); var trueStubs = from Stub s in sc where s.tf select s; n = trueStubs.Count(); sw.Stop(); MessageBox.Show("n:" + n.ToString() + " timer:" + sw.ElapsedMilliseconds.ToString()); </code></pre> <p>it works (little slower than foreach)</p> <p>plinq:</p> <pre><code>Stopwatch sw = new Stopwatch(); Int32 n = 0; sw.Start(); var trueStubs = from Stub s in sc.AsParallel() where s.tf select s; n = trueStubs.Count(); sw.Stop(); MessageBox.Show("n:" + n.ToString() + " timer:" + sw.ElapsedMilliseconds.ToString()); </code></pre> <p>100% CPU, no result</p> <p>why? the only difference is the AsParallel()</p>
 

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