Activator performance improvement

Shouldn't close the previous PR early. Turns out I did not have to change much of my design.

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@pranavkm
@halter73 
@rynowak
@ipjohnson
@yishaigalatzer 
Of course, but changes on the serviceProvider will reflect on MVC throughput. I am not saying we should rely on it for ever. We will need to design a test on serviceProvider next to track its performance in detail.