What is mscorsvw.exe and why is it eating up my CPU? What is this new CLR Optimization Service?

[Update – 8/2013]  Please refer to our more recent post: Wondering why mscorsvw.exe has high CPU usage? You can speed it up. The content below is now out-of-date, applying to early versions of the .NET Framework running on Windows XP.    Short version: mscorsvw.exe is precompiling .NET assemblies in the background. Once it’s done, it will…

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