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POWhy isn't ThreadPool.GetAvailableThreads working?
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copied!<p>I have a method to process the rows from a datatable using multiple threads, it queues up all the work items and then checks that they have all been processed, not leaving the method until they have.</p> <p>It seems to work fine in development, but when I put in onto the server (64-bit) for testing, it will not wait at the end of the method. It doesn't even seem to do the Thread.Sleep() calls, as the method exits straight away.</p> <p>It will continue to process the datarows after leaving the method, but that's not what I want.</p> <p>Any ideas? Thanks</p> <pre><code>Public Sub ProcessAll(ByVal collection As DataTable, ByVal processDelegate As WaitCallback) Dim workItem As DataRow Dim availableThreads As Integer Dim completionPortThreads As Integer ThreadPool.SetMaxThreads(MAX_THREADS, MAX_THREADS) ' loop round processing each pending record adding them to the Thread Queue For Each workItem In collection.Rows ThreadPool.QueueUserWorkItem(processDelegate, workItem) Next ' The ThreadPool is a collection of background threads, thus we need to do something to stop the main thread from moving on Do Thread.Sleep(1000) ThreadPool.GetAvailableThreads(availableThreads, completionPortThreads) ' in the case that all threads are free (how we check all are complete) wait a few seconds just to make sure If availableThreads = MAX_THREADS Then Thread.Sleep(5000) ThreadPool.GetAvailableThreads(availableThreads, completionPortThreads) End If Loop While availableThreads < MAX_THREADS End Sub </code></pre>

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