tcp reset connection by peer

Question

I have a problem launching multiple go routines over 90000 to do http requests via POST to the same server, both the server and the client are locally, some of the requests are executed successfully and some of them giving me this response read: connection reset by peer

Please notice I am posting a small amount of data in the provided example but actually I am sending a huge amount of data using protobuf.

This is the server https://play.golang.org/p/r1-rYNuAos

package main

import (
    "net/http"
    "log"
    "encoding/json"
)

var port string

type problem struct{
}

func main() {
    p := &problem{}
    p.server(":9090")
}

func (self *problem)server(port string) {
    s := &http.Server{
        Addr:           port,
        Handler:        self,
    }
    log.Println("Server started")
    // Should be last line as it is a blocking.
    log.Fatal(s.ListenAndServe())
}

func (self *problem) ServeHTTP(w http.ResponseWriter, r *http.Request) {
    w.Header().Set("Content-Type", "application/json")
    w.WriteHeader(http.StatusCreated)
    if err := json.NewEncoder(w).Encode(map[string]interface{}{"created": true}); err != nil {
        log.Fatal(err.Error())
    }
}

And this is the client https://play.golang.org/p/Xx5qQoqrYm

package main

import (
    "net/http"
    "bytes"
    "io/ioutil"
    "log"
    "fmt"
)

type problem struct{
}

func main() {
    p := &problem{}
    p.client(":9090")
}

func (self *problem)client(port string) {
    var k int

    for k=0;k<90000;k++ {

        go func(){

            nativeRequest, err := http.NewRequest(
                "POST",
                "http://127.0.0.1" + port + "/",
                bytes.NewBuffer([]byte(`testing`)),
            )

            nativeRequest.Close = true

            if err != nil {
                fmt.Println(err.Error())
            }

            client := &http.Transport{
            }
            nativeResponse, err := client.RoundTrip(nativeRequest)

            if err != nil {
                log.Println(err.Error())
            }

            if nativeResponse != nil {
                defer nativeResponse.Body.Close()

                if err != nil {
                        fmt.Println(err.Error())
                }

                body, err := ioutil.ReadAll(nativeResponse.Body)

                if err != nil {
                        fmt.Println(err.Error())
                }

                fmt.Println(string(body))
            }
        }()
    }
}