Исходники и презентации

lessons/strings/leak_with_string/main.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"fmt"
+	"runtime"
+	"unsafe"
+)
+
+func printAllocs() {
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+	fmt.Printf("%d MB\n", m.Alloc/1024/1024)
+}
+
+func findSequence(data string) string {
+	for i := 0; i < len(data)-1; i++ {
+		if data[i] == '\n' && data[i+1] == '\t' {
+			return data[i+2 : i+22]
+		}
+	}
+
+	return ""
+}
+
+func main() {
+	data := make([]byte, 1<<30)
+	// let's imagine that data was read from a file
+
+	str := unsafe.String(unsafe.SliceData(data), len(data))
+	sequence := findSequence(str)
+	_ = sequence // using of sequence later
+
+	printAllocs()
+	runtime.GC()
+	printAllocs()
+
+	runtime.KeepAlive(data)
+}