Comment by winrid
21 hours ago
The main benefit of python to me is that while slow, it's predictable. I do think they're going to get a lot more resistance to adding JITs, moving GCs, etc. it will become java with a million knobs to tune. If people want a JIT'd python just use pypy, right?
Java lost almost all those knobs a while ago (I mean they're there, but you're better off relying on the defaults). The modern GCs have one or at most two knobs remaining, and even that will become unnecessary next year. As to predictablity, you get maximal pause time of well under 1ms for heaps up to 16TB.
The max pause time thing is a meme :) I have gotten multi second pause times with ZGC. It depends on what hardware you run it on.
The new generational ZGC? I'm sceptical.
Have a reproducer?
As far as I know, java has 7 GC implementations, none of which are perfect, all of which have drawbacks
Lately, they seems to work with CRIU, various heuristics, multi-stage in-process bytecode compilation ..
Java is a mess, they are working hard to avoid fixing their issue (that nobody else have, so fixes are available)
>As far as I know, java has 7 GC implementations, none of which are perfect, all of which have drawbacks
Compared to Python's, all of them are beyond perfect. And 99.9% of the time you don't even need to use anything but the default.
4 replies →
Next year? Do tell
https://openjdk.org/jeps/8377305
As Python using SRE and supporting Python Flask apps, most of us would love JIT in Python assuming it pretty much drop in replacement.
PyPy doesn't have the support it needs and is stuck on 3.11.
PyPy is not looking healthy right now - it's several versions behind in support and, while it's not dead, it looks like it might be settling down for a rest.
Obviously it's not easy to move the whole language of a big codebase, but I feel a lot of this stuff (fiddling with GC, JITing, type hints, and I'm dubious about the free-threading stuff) tries to take Python somewhere it isn't really good at, and if that's what you want, you really want a different language.
Why not just use Go? It has a proper concurrent, non-moving GC that, AIUI, has not been associated with sudden memory spikes.
For a new project, teams can decide whether to use Go, but there are many millions of lines of existing Python servers out there.
Not to mention that there are differences in ecosystem, familiarity, and ergonomics that may make a team want to stick with Python.
“Just use Go” is not really actionable advice in most cases.
Libraries. I use both languages, and a survey of what libraries are available is part of picking an implementation language when starting a greenfield project.
It's a tradeoff. Go programs are extremely slow at starting up for example.
What? Compared to Python they're like lightning. Typically milliseconds to the start of main() - admittedly they can be slowed down by init() nonsense and terrible generated protobuf code nonsense in deep dependency trees - but with a non-trivial Python program you can look forward to an order of magnitude more. There are techniques to help address that but (1) they're not idiomatic and (2) it still only mitigates it.
I suppose Go programs are slower than the equivalent thing in C or C++, but I'm not sure that's a very relevant comparison in most cases today (how many new things being written would choose those languages).
So are Python and Java programs.
That doesn't matter for anything other then CLIs.
It is the same for me. Predicability is better than any optimization.
And if people want python with java, there's always Jython.
Graal vm has support for python 3 unfortunately it’s funded by oracle.
If it makes you feel any better (it probably doesn't), the development of OpenJDK and the Java language itself is also mostly funded by Oracle
Java is funded by Oracle, all of it.
People parrot to use OpenJDK without understanding it is mostly Oracle employees working on it.
And if you dislike Oracle, the other minor contributors are Red-Hat, IBM, SAP, Microsoft, Alibaba, Azul,... which for many HNers are the same.
jython has been basically unmaintained for quite some time
Well, they never made the jump to Python 3. But shipping 2.7 interpreters in 2024 was quite an achievement on its own. So their users already know this pain. And from my experience in academia, python 2.7 and java 8 will probably be used for another 20 years before the last machine running that stuff burns out.
Jython is unmaintained, I'd recommend Clojure. Use python libraries and code while seamlessly targeting the JVM.
jpype and graalpy are life.
jython went EOL.with python 2 going EOL.
In what way do you feel Python is predictable, especially in comparison to other languages one would build a backend system in?
It's predictable vs Rust, C#, F#, Elixir, Go, etc.?
Resistance from anyone who matters to the developers?