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What is considered a small object in C ++?

I read about the distribution of small objects in "Modern C ++ Design". Andrei Alexandrescu claims that general-purpose operators (new and remote) do not work well for allocating small objects.

In my program there are many objects created and destroyed in a free store. These objects measure over 8000 bytes.

What size is considered small? Are 8000 bytes small or large when it comes to memory allocation in C ++?

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The definition of “small” changes, but, generally speaking, an object can be considered “small” if its size is smaller than the overhead in size caused by the distribution of the heap (or at least close to this size).

Thus, a 16-byte object is probably considered "small" in most cases. A 32-byte object can be considered small under certain special circumstances. An 8,000-byte object is definitely not "small."

Usually, if you are faced with the problem of using a small allocator object, you want to improve the performance of some block of code. If using a small object allocator doesn't help your performance, you probably shouldn't use it.

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