Show memory stats in debug

cmd/sing-box/debug.go

@@ -5,11 +5,36 @@ package main
 import (
 	"net/http"
 	_ "net/http/pprof"
+	"runtime"
 
 	"github.com/sagernet/sing-box/log"
+
+	"github.com/dustin/go-humanize"
+	"runtime/debug"
+	"encoding/json"
+	"github.com/sagernet/sing-box/common/badjson"
 )
 
 func init() {
+	http.HandleFunc("/debug/gc", func(writer http.ResponseWriter, request *http.Request) {
+		writer.WriteHeader(http.StatusNoContent)
+		go debug.FreeOSMemory()
+	})
+	http.HandleFunc("/debug/memory", func(writer http.ResponseWriter, request *http.Request) {
+		var memStats runtime.MemStats
+		runtime.ReadMemStats(&memStats)
+
+		var memObject badjson.JSONObject
+		memObject.Put("heap", humanize.Bytes(memStats.HeapInuse))
+		memObject.Put("stack", humanize.Bytes(memStats.StackInuse))
+		memObject.Put("idle", humanize.Bytes(memStats.HeapIdle-memStats.HeapReleased))
+		memObject.Put("goroutines", runtime.NumGoroutine())
+		memObject.Put("rss", rusageMaxRSS())
+
+		encoder := json.NewEncoder(writer)
+		encoder.SetIndent("", "  ")
+		encoder.Encode(memObject)
+	})
 	go func() {
 		err := http.ListenAndServe("0.0.0.0:8964", nil)
 		if err != nil {