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Good to know. I use LuaJIT. But in any case I reverted that, befitting the overhead from my solution to Lua’s native was big.

> I’m not sure what point you’re trying to make,

Have you skimmed the linked thread?

> especially simulation/sampling approaches that are bound by the number and quality of uniform variates per second

Sorry, nobody does stochastic simulations where the number of uniform random numbers obtained per second is any sort of bottleneck. If you've spent considerable time on stochastic simulation, you already know this.

But even if you insist that you alone are doing some very weird stochastic simulation which is somehow bottlenecked on sourcing random numbers fast enough, the falling in planes phenomenon linked above would make xorshift-type generators a poor choice for most sorts of simulations. It introduces spatial correlations into any sort of lattice dynamics simulation (Ising model, percolation) and every high dimensional Monte Carlo integration. Beyond falling in the planes, since xorshift is linear over GF(2), it is also a particularly bad choice for nondeterministic cellular automata and Boolean dynamical systems which use parity, bit masks, or xors.

AES-CTR throughput on a modern CPU is higher than that of xoshiro256++, and much higher quality. No advances in non-CS PRNGs can beat that while maintaining the same quality. If your stochastic simulation is bottlenecked on random bits, CSPRNGs are still the way to go, and they don't interact in nasty ways with any dynamical system you can actually sinulate quickly.

> Not every system has the need or the resources to maintain a secure random sequence.

I'm sure there's something, but that category has to be shrinking every year. What does such a system look like this decade, that needs random numbers but can't easily implement something like AES?

> You may also want a reproducible pseudo-random sequence in generative code that logs the seeds. Because of the misguided attitude that nobody needs these features, everyone who does need them has to roll their own now.

I don't know what difficulty you're referring to. Basically every CSPRNG can be seeded easily and you can log the seed.

I agree! For many games (especially the ones running on old devices), xorshifts are pretty good! Not all applications need cryptographically safe generators! And sometimes it's ok to trade complexity for speed!

But I agree that if you're building something new aimed for modern devices, Marsaglia's xorshift128 wouldn't be my first choice! But I'd definitely want it in my RNG library for backward compatibility!

I should be faster next time then: my entry got tagged as [dupe] ahah! Also: I somehow got 10x the usual amount of traffic today, and my website is sort of on fire!

Then I am very sorry about that, I feel bad and should read more carefully next. I only glanced at first few paragraphs and encountered this line which is a very common LLM trope. I could see that article is long and has lots of images and other stuff but I could see em dashes too. As no one else had said that yet, I did.

But I do want to say that this 'witch hunt' is OK. We should keep calling out AI content which is mostly effortless to keep actual effort by humans separate from this flood of content.

I enjoyed the article, and thank you for sharing it. Don't be demotivated by the current AI witch hunt, which I see as a form of tribal signaling that will pass.

This is unbelievably good work, thank you for writing it!

Same - very good article.