Should I store entire objects, or pointers to objects in containers?

Question

Designing a new system from scratch. I\'ll be using the STL to store lists and maps of certain long-live objects.

Question: Should I ensure my objects have copy co

Answer 1

This question has been bugging me for a while.

I lean to storing pointers, but I have some additional requirements (SWIG lua wrappers) that might not apply to you.

The most important point in this post is to test it yourself, using your objects

I did this today to test the speed of calling a member function on a collection of 10 million objects, 500 times.

The function updates x and y based on xdir and ydir (all float member variables).

I used a std::list to hold both types of objects, and I found that storing the object in the list is slightly faster than using a pointer. On the other hand, the performance was very close, so it comes down to how they will be used in your application.

For reference, with -O3 on my hardware the pointers took 41 seconds to complete and the raw objects took 30 seconds to complete.