Is it required to reset the shared_ptr object initialized in a function(local variable)? and global to the file?

Question

Initialized global static shared_ptr object and passed to a function:

#include <iostream>
#include <memory>

std::shared_ptr<int> globalObj = std::make_shared<int>(5);

int testFunc(std::shared_ptr<int> obj1) {
    std::shared_ptr<int> localObj = obj1;
    std::cout<<"localObj.count:" << localObj.use_count() << std::endl;
    std::cout << "localObj:" << *localObj <<std::endl;
    localObj.reset();  -->** is it necessary to reset local count??**
    std::cout<<"localObj.count:" << localObj.use_count() << std::endl;
    return 0;
}

int main()
{
    std::cout<<"globalObj.count:" << globalObj.use_count() << std::endl;
    std::cout <<"globalObj:" << *globalObj <<std::endl;
    
    testFunc(globalObj);
    
    std::cout<<"globalObj.count:" << globalObj.use_count() << std::endl;
    std::cout <<"globalObj:" << *globalObj <<std::endl;
    
    globalObj.reset(); --> **is it necessary to reset global count??**
    std::cout<<"globalObj.count:" << globalObj.use_count() << std::endl;

    return 0;
}

globalObj.count:1
globalObj:5
localObj.count:3
localObj:5
localObj.count:3
globalObj.count:1
globalObj:5
globalObj.count:1

Does reset() affect the efficiency of the C++ program?

Answer 1

There is no need to reset, No.
The goal of the smart pointers: unique_ptr, shared_ptr and weak_ptr is to make automatic the release of the memory, through RAII concept.

Releasing the smart pointer is, consequently, pointless in 99.9% of the cases.

Here is an example of your code with few clarifications:

#include <iostream>
#include <memory>

class MyInt;
auto globalObj = std::make_shared<MyInt>(5);

class MyInt final
{
    int intVal;
public:
    MyInt()
    {
        std::cout << "Constucted!" << std::endl; 
    }
    
    MyInt(int nv ): intVal(nv)
    {
        std::cout << "Constucted!" << std::endl;
    }
    operator int()
    {
        return intVal; 
    }
    ~MyInt()
    {
        std::cout << "Destroyed!" << std::endl;
    }
};

int testFunc(const std::shared_ptr<MyInt>& obj1) 
{
    using std::cout;
    using std::endl;
    
    auto localObj = obj1;
    cout<<"localObj.count:" << localObj.use_count() << endl;
    cout << "localObj:" << *localObj << endl;
    return 0;
}

int main()
{
    using std::cout;
    using std::endl;
    
    {
    cout<< "globalObj.count:" << globalObj.use_count() << endl;
    cout << "globalObj:" << *globalObj << endl;
    
    testFunc(globalObj);
    
    cout << "globalObj.count:" << globalObj.use_count() << endl;
    cout << "globalObj:" << *globalObj << endl;
    }

    return 0;
}

Output:

Constucted!
globalObj.count:1
globalObj:5
localObj.count:2
localObj:5
globalObj.count:1
globalObj:5
Destroyed!

You can test it here: https://onlinegdb.com/tXqnoysmT