Actix-web: possible memory leak

[shaitao]

I build a server with Actix-web 2.0, and the memory was increasing with the increasing of requests. I don't know where is the problem, I just used awc(with tls), web. when I change all things to warp the problem is gone. I don't know how to find it.

[robjtede]

@shaitao you'll need to provide us with a minimal example so we can help

[Lesiuk]

My actix server is leaking memory when It's behind nginx (using proxy_pass). And everything is fine when connecting to directly. It's like few megabytes per 3000 requests. I will work on minimal reproduction example this weekend.

[pythoneer]

@Lesiuk is this related to your recent issue in https://github.com/actix/actix-web/issues/1446 ?

[Lesiuk]

@pythoneer yes, It's this issue and during investigation I was debugging a little a didnt found any other major leak

[robjtede]

wait, this issue was filed before the release of actix-rt 1.1 so can't be the same issue right?

[nazar-pc]

For me with 2.0.0 even this simple example leaks memory:

HttpServer::new(|| App::new().route("/", web::get().to(HttpResponse::Ok)))

Tested like this:

ab -c 100 -n 100000 http://localhost:8081/

With above command process consumes 315M of memory, with second call 626M, with third 939M, you get the idea.

Behavior is the same with both debug and release build.

I think this is quite a critical issue, surprised not many people have noticed it.

[Lesiuk]

Unfortunately I cannot reproduce it. Could you give us more info? Which operating system are you using? Actix-rt version?

[nazar-pc]

Ubuntu 20.10 (development branch), actix-rt 1.1.0.
Updating to actix-rt 1.1.1 seems to fix the issue for me.

[Lesiuk]

@nazar-pc thats the reason why actix-rt 1.1.0 was yanked https://github.com/actix/actix-net/issues/129

[nazar-pc]

Yeah, but I had it in lock file, so it installed fine anyway.
Unless there is additional evidence I believe this issue can be closed.

[jtescher]

This is also likely related to https://github.com/actix/actix-web/issues/1464

[singggum3b]

I'm also played with basic actix http2 3.0.0-alpha.3 and also notice some kind of memory leak
Simple h2 server reponse with some json literal:

pub async fn get_post() -> Result<HttpResponse> {
    Ok(HttpResponse::Ok().content_type("application/json").body(r#"{
    "glossary": {
        "title": "example glossary",
        "GlossDiv": {
            "title": "S",
            "GlossList": {
                "GlossEntry": {
                    "ID": "SGML",
                    "SortAs": "SGML",
                    "GlossTerm": "Standard Generalized Markup Language",
                    "Acronym": "SGML",
                    "Abbrev": "ISO 8879:1986",
                    "GlossDef": {
                        "para": "A meta-markup language, used to create markup languages such as DocBook.",
                        "GlossSeeAlso": ["GML", "XML"]
                    },
                    "GlossSee": "markup"
                }
            }
        }
    }
}"#))
}

#[actix_rt::main]
async fn main() -> io::Result<()> {
    Server::build()
        .bind("hello", "127.0.0.1:8081", || {
            HttpService::build()
                .h2(map_config(
                    App::new().service(web::resource("/").route(web::to(get_post))),
                    |_| AppConfig::default(),
                ))
                .tcp()
        })
        .expect("Failed to start server")
        .run()
        .await
}

h2 load:
h2load -n1000000 -c1000 -m1000 -v http://localhost:8081
Strange thing is cargo run can survive the load , while cargo run --release is noticeable slower and hang my mac in the end

[robjtede]

Tenatively fixed with #1580.