GOMAXPROCS

test-mc.go

package main

import (
    "fmt"
    "log"
    "net/http"
    "time"
    "runtime"
)

func main() {
    /*
     * print default GOMAXPROCS. See below.
     * - https://golang.org/pkg/runtime/#GOMAXPROCS
     * - https://docs.google.com/document/d/1At2Ls5_fhJQ59kDK2DFVhFu3g5mATSXqqV5QrxinasI/edit
     * - https://dave.cheney.net/tag/gomaxprocs
     * - https://morsmachine.dk/go-scheduler
     */
    fmt.Printf("current GOMAXPROCS is %d\n", runtime.GOMAXPROCS(0))
    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        if len(r.FormValue("case-two")) > 0 {
            // when using http://localhost:8000/?case-two=true
            fmt.Println("case two")
        } else {
            // when using http://localhost:8000/
            fmt.Println("case one start")
            time.Sleep(time.Second * 5)
            fmt.Println("case one end")
        }
    })

    if err := http.ListenAndServe(":8000", nil); err != nil {
        log.Fatal(err)
    }
}