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Comment by lunias

1 day ago

You appear to have been traumatized by Java... You can sub in any statically typed, compiled language.

The key distinction between multiprocessing and multithreading is that in multithreading all the threads of a process share the same memory. Are you saying that Python uses pipes for providing shared access to memory across processes? It looks like there is: multiprocessing.shared_memory, but this all seems more complicated than it is in other languages. Perhaps it's not?

I will 100% give you that Python has more libraries, but that's the only real advantage I was able to glean.

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lunias

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ActorNightly  1 day ago

No im saying that you can transport data over unix sockets, which are in memory, and python has that as part of multiprocessing.

The way python multiprocessing is set up is that it acts like a thread - when you launch a function, it copies the memory of the current process into the new one. You pay the startup overhead, so instead you launch worker processes ahead of time, and transport data to them over unix pipes. Pretty much almost as fast as threading.

>You appear to have been traumatized by Java

Not really, I just have standards. Java is just a poorly designed language with poor community support. Look at the amount of code it takes to send an HTTP request in Java, versus Python.

  • lunias  1 day ago

    > it copies the memory of the current process into the new one

    And if that memory is large enough then you OOM, so you would have to manage shared memory separately to prevent it from being copied into each process. It's not impossible, just complicated for some use-cases where using threads is a preferable paradigm.

    > Look at the amount of code it takes to send an HTTP request in Java, versus Python

    This is kind of my point.... (Java)

        var client = HttpClient.newHttpClient();
    var request = HttpRequest.newBuilder().uri(URI.create("https://api.example.com/data")).build();
    var response = client.send(request, HttpResponse.BodyHandlers.ofString());

    versus (Python)

        response = requests.get('https://api.example.com/data')

    Yes, it's more verbose, but not to the extent that I'd trade the compiler and performance for the less verbose version especially considering auto-complete in IDEs.

    • ActorNightly  1 day ago

      >And if that memory is large enough then you OOM

      OOM is not an issue these days lol. Memory is dirt cheap, and the amount of memory that gets copied is miniscule per process.

      There is still also the design of the application, just like with threading.

      >(Java)

      Forgetting the main class there, and also any additional headers that you need to send.

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