Understanding modern processor design

In the early days of computing, processors were relatively simple circuits. They could perform a single operation in exactly the order as provided by the programmer. Modern processors are an entirely different kind of beast. They have multiple cores, each running multiple threads, with instructions that perform multiple operations at once, with some instructions operating on multiple data at once. Moreover, they achieve this with incredible speed; even a relatively pedestrian 3GHz gives a single clock cycle of less than half a nanosecond (). With all this power at their disposal, modern processors can complete tasks with incredible speed.

Of course, being C++ programmers, we want to make sure that we use as much of this power as possible to complete our tasks as quickly as possible. Understanding the features of the processor and designing algorithms that are amenable to the processor will greatly accelerate your code. However, remember that...