containerFactory: useRunc ?

I would like to ask what is the function of this parameter. Will the performance decrease after running runc? If it is false, what is the underlying virtualization technology used by the function?

Locate the containerFactory implementation and its useRunc parameter, then trace where the parameter changes container execution. Document what runc does, any performance implications, and which virtualization or container technology is used when it is false; verify the explanation against the relevant runtime behavior.

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