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Comment by fwlr | Hacker News Reader

That is a fair point. I don’t think it saves this particular analysis, of course. Probably what’s important to know is something we might call the “Pareto naive performance”; with just a little bit of effort (the first 20% or so), you can get some significant performance improvement (the first 80% or so). Even the naive programmer just banging together something that works in Elixir is going to quickly find out how to raise Erlang’s default 260k process limit when they hit that, after all.

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Trying to raise the limit, but it didn't work:

    $ /usr/bin/time -v elixir --erl "-P 10000000" main.exs 1000000

    08:42:56.594 [error] Too many processes
    ** (SystemLimitError) a system limit has been reached

Any other ideas how to raise the limit?

I asked ChatGPT and it said

“This limit can be adjusted with the `+P` flag when starting the BEAM… To adjust the limit, you could start the Elixir application using a command like the following:

    elixir --erl "+P 1000000"

“If you are getting this error not because of the BEAM limit, but rather because of your operating system limit (like the limit on the number of open files or the number of child processes), you will need to look into how to increase these limits on your specific operating system.”

Yes, again ChatGPT was better than just random search. If writing this blog post teaches me something, then it teaches me to use ChatGPT more not less ;)

BTW, I fixed the 1M benchmark and Elixir is included now.

I’m glad you saw the irony in my reply. I was a little worried it would come off acerbic, like “since you use ChatGPT, you only deserve ChatGPT”. The real intent was double-edged, of course - to demonstrate that ChatGPT isn’t just dumb-codemonkey-as-a-service, it can also quite easily solve a lot of the problems it is purported to create. You have been handling mean comments here (including my own mean comments) with grace, so I took the risk.

> Even the naive programmer just banging together something that works in Elixir is going to quickly find out how to raise Erlang’s default 260k process limit when they hit that, after all.

Sure. Will redo this part. I doubt it would allow Elixir to get a better result in the benchmark, though, as it was already losing significantly at 100k tasks. Any hints on how to decrease Elixir memory usage? Many people criticize using defaults in the comments, but don't suggest any certain settings that would improve the results. And a part of blogging experience is too learn things - also from the author perspective ;)

    1..num_tasks
      |> Task.async_stream(fn _ ->
          :timer.sleep(10000)
        end, max_concurrency: num_tasks)
      |> Stream.run()

https://elixirforum.com/t/how-much-memory-do-you-need-to-run...

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