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Comment by DoesntMatter22 | Hacker News Reader

Elixir is slower than plain PHP according to the techempower benchmarks. I'm not even sure how that's possible but it is. By like a factor of 2 iirc. I'm not sure how elixir is that slow since it's compiled.

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The techempower benchmark are... Quite infamous in the elixir community.

Long story short, they are running in debug mode, badly written, not optimised, with bad OS level settings. And every time the community have tried to contribute fixes, the experience has been... Really bad.

So we stopped trying. If things have changed we could try again but ... We just wrote them off

As far as I can tell, you’re basing this off a single thread from a prior techempower round. The result being cleaned up in a subsequent round, but are ignoring that.

It depends on what is actually being benchmarked though; if it's the simple JSON payload, more time will be spent on HTTP parsing (done in nginx for the PHP benchmark so really really fast) and some JSON parsing (done in a C library for the PHP benchmark so really really fast). Basically, how much PHP is actually being benchmarked?

Are you looking at a benchmark that compares real-world usage, or a microbenchmark like hello world or a small JSON payload?

That's a reasonable point. This is Techempower as I mentioned originally. In pretty much all the benchmarks PHP smokes Elixir

>Elixir is slower than plain PHP according to the techempower benchmarks. I'm not even sure how that's possible but it is.

You're "Not even sure how that's possible" as if implying PHP is slow?

Even old pre-7 PHP was much faster than Ruby, Python, and others. And most PHP libs are just wrappers over C code.

> Even old pre-7 PHP was much faster than Ruby, Python, and others.

No, PHP 7 was an impressive step forward in speed because it switched to better bytecode and object representations internally, but Python wiped the floor with most versions of PHP 5 for exactly the same reason. (PHP 5.5 with opcaching was roughly comparable.)

But this comparison overall is like trying to find the strongest two-year-old...

It's a ridiculous thing to say that any version of PHP is slow. You could run PHP5 today and it's still not slow by any modern standard. Even on the hardware of 15 years ago almost any script you throw at it finishes in single digit milliseconds.

How is that slow? I'd like to meet the developers that consider this slow.

I guess it depends on what the script is doing, but I'd consider that slow. Code I've worked on in Scala takes more like 50-60 microseconds per http request for a json CRUD type of thing (plus latency to wait for the db, but it can serve other requests during that time).

Ladies and gentlemen, the strongest two-year-old.

The strongest within a certain category is still a useful concept.

If one is looking for a strong pickup truck, they don't care that a 18-wheeler is stronger, as that's in another category they have no use for.

One might want to pick among "scripting languages with suitability for web coding and great adoption" for example...

Ruby and Rails especially, aren't fast in terms of fast running programs. But they are fast in terms of launching features quickly.

Playing with Elixir, I feel similar speed of development, but it also comes with speed of running, which is incredible.

PHP is interpreted and Elixir is compiled. Comparing them to Ruby and Python make no sense as they are interpreted as well.

The fact that Elixir, a compiled language, known for speed, is slower than PHP is surprising. As far as "Most PHP libs are wrappers over C code". That's just not true. Most PHP libs are in PHP

>PHP is interpreted and Elixir is compiled. Comparing them to Ruby and Python make no sense as they are interpreted as well.

The metric is speed. Compiled vs interpreted is an implementation concern.

You can be compiled and slower than interpreted (and vice versa).

>The fact that Elixir, a compiled language, known for speed

Elixir is not compiled into binary. It's compiled to bytecode for the BEAM vm.

And Elixir was never known for speed, nor was Erlang. They are known for parallelism, availability, fault tolerance, smart schedulling, etc.

Because they are different languages with different VMs and different concerns. Made for different purposes. Number crunching is slower in Erlang VM (you can call C code though).

PHP is fast these days raw-speed wise. Concurrency and parallelism matter more than speed as they translate directly to utilisation.

Yes, calling something Fast can mean many different things. Erlang/Elixir are not 'fast' at number crunching, but they are very good at concurrency.

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