This problem usually appears randomly but it can also occur after an update is installed to .NET Framework. The process’s executable is mscorsvw.exe and it will be displayed in Task Manager under that name or as .NET Runtime Optimization Service. It doesn’t run so often and it’s a service that runs to optimize .NET Framework which, in return, makes sure apps and programs dependent on it run faster.
The official answer is that the process needs to recompile its libraries and that it should only run when the computer is idle. Microsoft also states that the process shouldn’t take more than a couple of minutes.
It’s not recommended to end this process immediately.
Optimizing the process :
1st way
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//on x86 sytems
cd c:\Windows\Microsoft.NET\Framework\v4.0.30319
//on x64 systems
cd c:\Windows\Microsoft.NET\Framework64\v4.0.30319
ngen.exe executequeueditems
2nd way (microsoft github repository)
Download by click ‘raw’ then right-click ‘save as’ then double click the file to run you can use the WSF https://github.com/Microsoft/dotnet/blob/master/tools/DrainNGENQueue/DrainNGenQueue.wsf
for advanced users there is also a Powershell sccript: https://github.com/microsoft/dotnet/blob/master/tools/DrainNGENQueue/DrainNGenQueue.ps1
src - https://appuals.com/fix-high-cpu-usage-by-net-runtime-optimization-service/
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