Draft

Let me start out by saying this proposal doesn't propose that support be dropped for IMultithreaded* interfaces. This proposal does propose that they should be marked as deprecated and over time channels should be rewritten to use IChannel instead. Also, we need to make it clear that IMultithreaded* channels shouldn't be perceived as a better, faster more optimized way of developing a channel.

Complexity

That implementing Channels as IMultithreaded* makes for much more complex code is a serious problem in an open source project. It is a very serious barrier to collaboration, and this reason alone is enough to warrant deprecation.

In addition to the unneeded complexity there are some other problems with IMultithreaded* channels:

No Session Replication

They won't work with session replication as the static state map won't be serialized and replicated.

Potential Memory Leaks

They require the channel's implementation to remove objects from its map when a user's session is removed. This easily results in a channel that leaks memory if it fails to remove the objects from its map.

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