Design Pattern for Update changes to particular feature [closed]

I am noob in C++. I had a program where there are many features. When something is changed in any value of any feature it needs to update value. There is a loop which has to be called whenever there is a little change in a feature value and all features get updated too. This loop had made the program slow because for even a little value in x feature i have to refresh all values from a to z features. I wanted to know if there is some architecture or design pattern which could be helpful to update only that value in feature and don't need to update every feature.