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    <p>No more potential than a SingleCall component. Both will have problems if they attempt to access a shared memory location in an unsafe manner. </p> <p>The difference between SingleCall and Singleton is that, for SingleCall , every incoming request will get a new instance of the defined type created to handle that call. Each instance will have its own memory space and instance variables, but they can still share static and global variables, external resources, files, network connections, etc. If the SingleCall class is coded to access any shared memory state in a thread-unsafe manner, then you will have issues. </p> <p>A Singleton, on the other hand, only gets one instance created for ALL incoming requests, so by definition, every instance variable in use within that singleton is, in fact, shared among all incoming requests. A good example might be a message publisher, that all code in the server needs to access to send messages to one or more subscribed clients....</p> <p>To address comment from @Cocowalla, make sure if you do this you override the method </p> <pre><code> MarshalByRefObject.InitializeLifetimeService() </code></pre> <p>as shown, or your singleton will die out unexpectedly if no one calls it for a while... </p> <pre><code>public class MessageManager : MarshalByRefObject { #region Singleton / MarshalByRefObject code private static MessageManager mgr = new MessageManager(); // creates singleton static MessageManager() { } private MessageManager() { } public static MessageManager Instance { get { return mgr; } } public override object InitializeLifetimeService() { return (null); } #endregion Singlelton code // ... other stuff ... } // in Remoting Host initialization code... MessageManager mgr = MessageManager.Instance; // generates singleton; RemotingServices.Marshal(mgr, URI); </code></pre>
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    1. POUsing Singleton vs Single Call in .NET Remoting?
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    1. USCharles Bretana
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    1. COYou will need to be wary of a Singleton's lifetime though - depending on your configuration, your Singleton that you expect to be around while the app is running can actually be automatically destroyed and recreated. In remoting, Singletons have a given 'lease' or 'lifetime', after which they will automatically be destroyed. It is possible to change the lifetime, or indeed to extend it indefinitely, but it's something to be aware of. Some more reading: http://www.thinktecture.com/resourcearchive/net-remoting-faq/singletonisdying http://msdn.microsoft.com/en-us/magazine/cc300474.aspx
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