How does ktor with Native embeddedServer CIO engine handle connections with zero length data? Does i...

# ktor

[Joakim Forslund]

How does ktor with Native embeddedServer CIO engine handle connections with zero length data? Does it automatically disconnect? I am having a somewhat odd memory allocation experience on a vm instance with limited resources, where these connections never seem to be freed.

[Joakim Forslund]

https://api.ktor.io/ktor-server/ktor-server-cio/io.ktor.server.cio/-c-i-o-application-engine/-configuration/index.html seems to say 45 seconds, but I'm seeing something odd, I'm not sure the memory footprint for these connections is ever freed properly

[Joakim Forslund]

This is without basically any real requests, just empty connections

[Joakim Forslund]

Dependencies for linux:
ktor-server-core - 2.1.2 (also tested with 2.1.3-eap-521)
ktor-server-cio - 2.1.2 (also tested with 2.1.3-eap-521)
kotlinx-coroutines-core - 1.6.4

all of this is running in a docker container with a load balancer in front

[Joakim Forslund]

Compared to if I roll a test http server built with zeromq that has the socket handler which just disconnects zero length data and give back a real http response if the data contains a proper http request (Comparing coroutines io vs classic blocking is not fair, but my hope is that it proves a point)

[Joakim Forslund]

data class Simple(val name:String, val nr:Int, val lnr2:Long, val status:Boolean)

fun main() {
    println("Trying to start server")

    val simple = Simple("Ape", 0, 1L, true)

    embeddedServer(CIO, port = 7878) {
        install(ContentNegotiation) {
            json(Json {
                prettyPrint = true
                isLenient = true
            })
        }
        routing {
            get("/status") {
                call.respond(HttpStatusCode.OK, simple)
            }
        }
    }.start(wait = true)
}

Is the code