goでメモリ使用量を調べる

memory.go

func main() {

	mem := func () uint64 {
		runtime.GC()
		var s runtime.MemStats
		runtime.ReadMemStats(&s)
		
		// Sys 以外にも [Alloc, TotalAlloc, Mallocs, Frees, HeapAlloc, HeapSys, HeapIdle, HeapInuse, HeapReleased, HeapObjects, StackInuse, StackSys, MSpanInuse, MSpanSys, MCacheInuse, MCacheSys, BuckHashSys, GCSys, OtherSys] などがある
		return s.Sys
	}

	before := mem()

	// ここにメモリを使う処理を書く

	after := mem()

	fmt.Printf("used memory: %.3fkb\n", float64(after - before))
}