Move heap example

examples/memory/main.go

@@ -0,0 +1,76 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/http"
+	_ "net/http/pprof"
+	"os"
+	"runtime"
+	"time"
+
+	"golang.org/x/sync/errgroup"
+)
+
+func main() {
+	if err := run(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func run() error {
+	runtime.MemProfileRate = 1
+
+	g, _ := errgroup.WithContext(context.Background())
+
+	g.Go(func() error {
+		addr := "localhost:6060"
+		log.Printf("Listening on %s", addr)
+		return http.ListenAndServe(addr, nil)
+	})
+
+	//g.Go(allocStuff)
+
+	// Memory leak that leaks 1 kB / sec at a rate of 10 Hz.
+	g.Go(func() error { return leakStuff(1024, 100*time.Millisecond) })
+	g.Go(func() error { return allocStuff(1024, 100*time.Millisecond) })
+	g.Go(func() error { return forceGc(time.Second) })
+
+	return g.Wait()
+}
+
+var leak []*Data
+
+// leakStuff leaks ~bytes every interval.
+func leakStuff(bytes int, interval time.Duration) error {
+	for {
+		leak = append(leak, newData(bytes))
+		time.Sleep(interval)
+	}
+}
+
+// allocStuff is allocating things but not leaking them.
+func allocStuff(bytes int, interval time.Duration) error {
+	for {
+		newData(bytes)
+		time.Sleep(interval)
+	}
+}
+
+// forceGc forces a GC to occur every interval.
+func forceGc(interval time.Duration) error {
+	for {
+		time.Sleep(interval)
+		runtime.GC()
+	}
+}
+
+func newData(size int) *Data {
+	return &Data{data: make([]byte, size)}
+}
+
+type Data struct {
+	data []byte
+}