log GC duration and set to 10min interval

src/core/forceGC.js

@@ -3,7 +3,10 @@
  */
 function forceGC() {
   if (global.gc) {
+    const startTime = Date.now();
     global.gc();
+    // eslint-disable-next-line no-console
+    console.log(`GC took ${Date.now() - startTime}`);
   }
 }
 

src/server.js

@@ -31,7 +31,7 @@ app.disable('x-powered-by');
 
 
 // Call Garbage Collector every 30 seconds
-setInterval(forceGC, 15 * 60 * SECOND);
+setInterval(forceGC, 10 * 60 * SECOND);
 
 // create http server
 const server = http.createServer(app);