A walkthrough of four mechanisms working behind every push_back() call — exponential growth and amortized O(1), the growth factor's effect on memory reuse, cache performance from contiguity, and the silent noexcept trap in move semantics during reallocation.

std::vector — Four Mechanisms Behind Every push_back()

by Gracjan Olbinski

From the article:

"You call push_back() a thousand times. The vector reallocates about ten. Behind that simple interface, four mechanisms are working together — each one invisible during normal use, each one shaping your performance in ways that push_back() will never tell you about."