go 主动调用 gc 没有起效果

go_call_gc.go

package main

import "fmt"
import "time"
import "runtime"

type User struct {
	name string
	age int
	des [10240]byte
}

func alloc(){
	all :=make([]*User, 100)
	for i:=0;i<1000000;i++{
		u := new(User)
		u.age = i
		all = append(all, u)
	}
}

func main() {
	alloc()
	var input int
	fmt.Scan(&input)
	fmt.Println(input)
	runtime.GC()
	fmt.Println("gc complete")
	
	for i:=0; i < 1000; i++ {
		u := User{}
		u.name = "alloc"
		time.Sleep(10*time.Second)
	}
}