Pitfalls of Performance Testing
Beware the casual performance test, it will lie to you. It is simple to write something that gives you timings, …
Category Archives: Efficiency
Performance is irrelevant
Asking questions about performance online universally invites scorn and accusation. A large number of programmers apparently feel that the efficiency …
How does a mutex work? What does it cost?
Concurrent programming requires synchronisation. We can’t have more than one thread accessing data at the same time otherwise we end …
How Polymorphism Works: Part 2: Virtual Table
In the article on “How Polymorphism Works: Part 1” we learned how to create virtual functions. The method which we …
How Polymorphism Works: Part 1
Polymorphism: the core of object oriented programming. Most modern languages have some concept of interfaces, virtual functions, and classes. Though …
What is an atomic operation?
We all know that operations in a computer happen one after the other. Having multiple CPUs and instruction reordering tends …
CPU Reordering – What is actually being reordered?
We’ve all heard that a CPU may reorder access to memory. Yet if you’ve looked further you’d also see that …
CPU Memory – Why do I need a mutex?
Multi-threaded programming calls for semaphores, synchronized blocks, mutexes, or whatever your language happens to call them. Most of us basically …
The Cost – A Function Call
In the grand scheme of execution costs function calls come very close to the bottom of the list. They don’t …
The Cost – Instantiation and the hidden enemy “new”
Whether C++, Java or any other language, we are all familiar with instantiating an object. In those aforementioned languages the …
