Please note that LoaderOptimization only affects how assemblies are loaded and shared across application domains (domain-neutral assemblies, and they can only be loaded from GAC). JIT-compiled code cannot be shared for assemblies loaded into the load-from context. .NET agent assemblies are JIT compiled, and will be loaded from the installed path using LoadFrom context.
Hence, we need to set this environment variable to force load .NET agent assemblies individually for every app domain. Only when you precompile your assemblies with NGen.exe (Native Image Generator), does this setting has any performance effect (additional memory usage due to loading multiple copies of domain-neutral assemblies).
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