From 94cc221625331b9bedb069814586c7c877a8fcc1 Mon Sep 17 00:00:00 2001
From: Jan-Lukas Else <mail@jlelse.de>
Date: Sat, 13 Mar 2021 13:17:42 +0100
Subject: [PATCH] Added regular garbage collection

---
 cache.go            |  5 -----
 garbagecollector.go | 24 ++++++++++++++++++++++++
 http.go             |  6 ------
 main.go             |  3 +++
 4 files changed, 27 insertions(+), 11 deletions(-)
 create mode 100644 garbagecollector.go

diff --git a/cache.go b/cache.go
index 071d075..f42b378 100644
--- a/cache.go
+++ b/cache.go
@@ -9,7 +9,6 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"net/url"
-	"runtime"
 	"strconv"
 	"strings"
 	"time"
@@ -211,10 +210,6 @@ func getCache(key string, next http.Handler, r *http.Request) (item *cacheItem)
 
 func purgeCache() {
 	cacheR.Clear()
-	// Do manual GC
-	go func() {
-		runtime.GC()
-	}()
 }
 
 func setInternalCacheExpirationHeader(w http.ResponseWriter, expiration int) {
diff --git a/garbagecollector.go b/garbagecollector.go
new file mode 100644
index 0000000..76ded2d
--- /dev/null
+++ b/garbagecollector.go
@@ -0,0 +1,24 @@
+package main
+
+import (
+	"log"
+	"runtime"
+	"time"
+)
+
+func initGC() {
+	go func() {
+		ticker := time.NewTicker(10 * time.Minute)
+		for range ticker.C {
+			go doGC()
+		}
+	}()
+}
+
+func doGC() {
+	var old, new runtime.MemStats
+	runtime.ReadMemStats(&old)
+	runtime.GC()
+	runtime.ReadMemStats(&new)
+	log.Printf("Alloc: %v MiB → %v MiB", old.Alloc/1024/1024, new.Alloc/1024/1024)
+}
diff --git a/http.go b/http.go
index 3c7c2ed..ec2ed0e 100644
--- a/http.go
+++ b/http.go
@@ -6,7 +6,6 @@ import (
 	"log"
 	"net/http"
 	"net/url"
-	"runtime"
 	"strconv"
 	"strings"
 	"sync/atomic"
@@ -90,11 +89,6 @@ func reloadRouter() error {
 	}
 	purgeCache()
 	d.swapHandler(h)
-	// Do manual GC
-	go func() {
-		time.Sleep(10 * time.Second)
-		runtime.GC()
-	}()
 	return nil
 }
 
diff --git a/main.go b/main.go
index 91ee25a..70b6c1e 100644
--- a/main.go
+++ b/main.go
@@ -52,6 +52,9 @@ func main() {
 		}
 	}
 
+	// Init regular garbage collection
+	initGC()
+
 	// Execute pre-start hooks
 	preStartHooks()
 	// Initialize everything else