Comment by mcronce | Hacker News Reader

Comment by mcronce | Hacker News Reader

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> every mainstream language with easy FFI still has significant FFI overhead (so much so that many programs actually run slower with FFI). This isn't really true for Rust

This isn't true for almost any language to the extent it's true for Go, and for many compiled languages it isn't really true at all.

> Try building a significant Python project on anything except a recent version of RHEL, Debian, MacOS, or Windows. For example, try getting your Python project running on something like a scratch Docker container. Or try packaging a Python package (which depends even transitively on a C library, especially one which isn't already packaged for Nix) with Nix.

While these are legitimate theoretical problems, none of them are really problems in practice. Containers don't need to be scratch, and if you're building a Python project, you're already not running a scratch container, so the addition of FFI doesn't change that. Nix is not an environment I've ever seen a requirement to support, let alone had a requirement.

It really seems to me that you like Go and you like Go's design decisions, but "I like this" is not the same as "this is better than that". I'm not particularly interested in rehashing the same conversation over and over again.

> This isn't true for almost any language to the extent it's true for Go

Go's object structure is much closer to C's. In many cases, it's just casting pointers (e.g., you can convert a Go slice to a C array by taking a pointer to its first element and casting it to a pointer of the C element type, provided the element types are binary-compatible). This means fewer allocations than a language like Java or Python where you would have to allocate a new slice and chase pointers around the heap for every field in every element in the array. In my experience, most of Go's overhead comes from function call bookkeeping at the FFI boundary rather than marshaling data.

> for many compiled languages it isn't really true at all.

I'm pretty sure it's still true for many compiled languages (e.g., Java, Haskell, etc).

> While these are legitimate theoretical problems, none of them are really problems in practice.

They were problems for me in practice.

> Containers don't need to be scratch, and if you're building a Python project, you're already not running a scratch container, so the addition of FFI doesn't change that.

Containers don't need to be scratch, but they often need to be lightweight with low cold-start latencies (including pulling). Not having to pull in a whole distro is advantageous. And a pure-Python project certainly could run in a scratch container (i.e., a container with just the interpreter, the program, and the program's transitive dependencies).

> Nix is not an environment I've ever seen a requirement to support, let alone had a requirement.

"Reproducible builds" is the requirement. Our customers' security teams vetted our dependencies individually, and if a dependency changed we would have to have that dependency re-vetted.

> It really seems to me that you like Go and you like Go's design decisions, but "I like this" is not the same as "this is better than that".

Clearly, no one here is conflating those things. I'm arguing that Go has a particular strength, not that that strength is the only factor.

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