Mirosoft made available STM.NET (with STM = software transactional memory), is an experimental enhanced version of .NET Framework 4 Beta 1 that enables software transactional memory for C# programmers. Transactional memory is a technology that frees developers from worrying about the mechanics of fine-grained locking and synchronization in multithreaded applications by providing transactional semantics for reading and writing to memory.  It enables developers to focus on application logic instead of the details of memory I/O when building multi-core and many-core programs.

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