diff --git a/src/engine/runtime.js b/src/engine/runtime.js
index afd930246..c51be795d 100644
--- a/src/engine/runtime.js
+++ b/src/engine/runtime.js
@@ -77,7 +77,7 @@ util.inherits(Runtime, EventEmitter);
 /**
  * How rapidly we try to step threads, in ms.
  */
-Runtime.THREAD_STEP_INTERVAL = 1000 / 30;
+Runtime.THREAD_STEP_INTERVAL = 1000 / 60;
 
 
 // -----------------------------------------------------------------------------