Cache lookup of macro by alias

src/Umbraco.Core/Cache/CacheKeys.cs

@@ -11,5 +11,6 @@
         public const string TemplateFrontEndCacheKey = "template";
 
         public const string MacroContentCacheKey = "macroContent_"; // used in MacroRenderers
+        public const string MacroFromAliasCacheKey = "macroFromAlias_";
     }
 }

src/Umbraco.Web/Cache/MacroCacheRefresher.cs

@@ -99,6 +99,7 @@ namespace Umbraco.Web.Cache
             return new[]
                 {
                     CacheKeys.MacroContentCacheKey, // macro render cache
+                    CacheKeys.MacroFromAliasCacheKey, // lookup macro by alias
                 };
         }
 

src/Umbraco.Web/Macros/MacroRenderer.cs

@@ -197,7 +197,8 @@ namespace Umbraco.Web.Macros
 
         public MacroContent Render(string macroAlias, IPublishedContent content, IDictionary<string, object> macroParams)
         {
-            var m = _macroService.GetByAlias(macroAlias);
+            var m = _appCaches.RuntimeCache.GetCacheItem(CacheKeys.MacroFromAliasCacheKey + macroAlias, () => _macroService.GetByAlias(macroAlias));
+
             if (m == null)
                 throw new InvalidOperationException("No macro found by alias " + macroAlias);