I recently stumbled upon this screenshot while researching social media on the train. Of course, it was followed by a cascade of spiteful comments, criticizing this fresh programmer’s attempt to solve a classical problem in computer science. The modulus operation.
I like this bit at the end:
Really makes you question your sanity when optimizing jumps in code without benchmarks.
For a long time I’ve been of the opinion that you should only ever optimize for the next
suckercolleague who might need to read and edit your code. If you ever optimize for speed, it needs to be done with massive benchmarking / profiling support to ensure that the changes you make are worth it. This is especially true with modern compilers / interpreters that try to use clever techniques to optimize your code either on the fly, or before making the executable.The first rule of optimization: Don’t do it
The second rule of optimization: Don’t do it yet (experts only)
I’m absolutely on-board …in application code.
I do feel like it’s good, though, when libraries optimize. Ideally, they don’t have much else to do than one thing really well anyways.
And with how many libraries modern applications pull in, you do eventually notice whether you’re in the Python ecosystem, where most libraries don’t care, or in the Rust ecosystem, where many libraries definitely overdo it. Because well, they also kind of don’t overdo it, since as a user of the library, you don’t see any of it, except the culmulative performance benefits.
Libraries are also written and maintained by humans.
It’s fine to optimize if you can truly justify it, but that’s going to be even harder in libraries that are going to be used on multiple different architectures, etc.
I’m still mad he didn’t use the size of the number to tell the system which block to read first. I feel like that would be a great use of division or maybe modulus?
I just like how he used “% 2” in the Python code he used to generate the C++ code.