Each module, and every function in every module is an atom. If you are loading a few libraries hitting 22K isn’t too hard. I’m not sure what to think of the memory. Its not so bad compared to other high-level language VMs though is it? I’m sure Go or Rust would be a lot smaller but a better comparison is Ruby, Python or Java.

70 MBs seems a bit high for a small app. What all libs are you loading?

The image below shows a basic Phoenix app.

image478×254 8.74 KB

If you do try building a release, I’m curious to see what the memory usage turns out to be. I made a quick comparison in a project of my own and also just a plain new phoenix project, in both cases memory use was much higher in the release. Why do releases use so much more memory than `mix run`?

As I point out though, my comparison may be unfair, as not all code is necessarily loaded in the mix version when I checked memory use, while releases preload all modules. But you should be able to get an accurate comparison.

makes sense!

Here’s my app:

$ mix deps.tree
app
├── statix ~> 1.1 (Hex package)
├── gen_stage ~> 0.14.0 (Hex package)
├── jason ~> 1.1 (Hex package)
├── poison ~> 4.0 (Hex package)
├── junit_formatter ~> 3.0 (Hex package)
├── dialyxir ~> 0.4 (Hex package)
├── hackney ~> 1.9 (Hex package)
│   ├── certifi 2.5.1 (Hex package)
│   │   └── parse_trans ~>3.3 (Hex package)
│   ├── idna 6.0.0 (Hex package)
│   │   └── unicode_util_compat 0.4.1 (Hex package)
│   ├── metrics 1.0.1 (Hex package)
│   ├── mimerl ~>1.1 (Hex package)
│   └── ssl_verify_fun 1.1.4 (Hex package)
├── sweet_xml ~> 0.6 (Hex package)
├── ex_aws ~> 2.0 (Hex package)
│   ├── hackney 1.6.3 or 1.6.5 or 1.7.1 or 1.8.6 or ~> 1.9 (Hex package)
│   ├── poison >= 1.2.0 (Hex package)
│   └── sweet_xml ~> 0.6 (Hex package)
├── ex_aws_sqs ~> 2.0 (Hex package)
│   └── ex_aws ~> 2.0.0 (Hex package)
├── credo ~> 1.0 (Hex package)
│   ├── bunt ~> 0.2.0 (Hex package)
│   └── jason ~> 1.0 (Hex package)
└── tesla ~> 1.2.1 (Hex package)
    ├── hackney ~> 1.6 (Hex package)
    ├── jason >= 1.0.0 (Hex package)
    ├── mime ~> 1.0 (Hex package)
    └── poison >= 1.0.0 (Hex package)

credo, dialyxir and junit_formatter are :dev or :test only.

Would the size of the loaded code change if I built a release instead of running plain mix run?