I import reqwest and the size of binary increase

[lz1998]

I import reqwest and do nothing else.

Run cargo build --release, and I found the size of binary is 274KB larger.

With reqwest

lz1998@lizhengdeMacBook-Pro ~/C/r/t/release (master)> ll                                                                                                                                                                                                                      (base) 
total 1800
drwxr-xr-x   68 lz1998  staff   2.1K Mar 17 01:55 build
drwxr-xr-x  513 lz1998  staff    16K Mar 17 01:57 deps
drwxr-xr-x    2 lz1998  staff    64B Mar 17 01:31 examples
drwxr-xr-x    2 lz1998  staff    64B Mar 17 01:31 incremental
-rwxr-xr-x    1 lz1998  staff   892K Mar 17 01:57 rs_test
-rw-r--r--    1 lz1998  staff   108B Mar 17 01:31 rs_test.d


Without reqwest
lz1998@lizhengdeMacBook-Pro ~/C/r/t/release (master)> ll                                                                                                                                                                                                                      (base) 
total 1248
drwxr-xr-x   68 lz1998  staff   2.1K Mar 17 01:55 build
drwxr-xr-x  480 lz1998  staff    15K Mar 17 01:56 deps
drwxr-xr-x    2 lz1998  staff    64B Mar 17 01:31 examples
drwxr-xr-x    2 lz1998  staff    64B Mar 17 01:31 incremental
-rwxr-xr-x    1 lz1998  staff   618K Mar 17 01:56 rs_test
-rw-r--r--    1 lz1998  staff   108B Mar 17 01:31 rs_test.d

main.rs

use axum::{response::Html, routing::get, Router};
use std::net::SocketAddr;

#[tokio::main]
async fn main() {
    // build our application with a route
    let app = Router::new().route("/", get(handler));

    // run it
    let addr = SocketAddr::from(([127, 0, 0, 1], 3000));
    println!("listening on {}", addr);
    axum::Server::bind(&addr)
        .serve(app.into_make_service())
        .await
        .unwrap();
}

async fn handler() -> Html<&'static str> {
    Html("<h1>Hello, World!</h1>")
}

Cargo.toml

[package]
name = "rs_test"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
axum = "0.4"
tokio = { version = "1.0", features = ["full"] }
# reqwest = "0.11"

[profile.release]
opt-level = 'z'
debug = false
lto = true
incremental = false
codegen-units = 1
strip = true

[davidpdrsn]

Excuse me but what does this have to do with axum?

[lz1998]

Excuse me but what does this have to do with axum?

If I import some crates in Cargo.toml and I don't use it in code, the size of binary will not increase. (This is expected.)

I wonder is there some internal macros which use reqwest in axum, and increase the size of binary.

[lz1998]

There are four cases:

1. Import axum and reqwest, and use none. (392KB)
2. Import axum, and use none. (392KB)
3. Import axum and reqwest, and use axum. (892KB)
4. Import axum, and use axum. (618KB)

• 1 and 2 should be same (expected)
• 3 and 4 should be same (not expected)

[davidpdrsn]

Please ask this question somewhere else. I have no idea about this 🤷‍♂️

[jplatte]

I would expect this to be due to reqwest enabling extra features on hyper, such as http2 support (which axum doesn't enable by default). You should see a similar size increase by enabling axum's http2 feature without the reqwest dependency, and no size increase from enabling the http2 feature on axum when reqwest is already a dependency.