diff --git a/Assets/SteamVR/Input/SteamVR_ActionSet_Manager.cs b/Assets/SteamVR/Input/SteamVR_ActionSet_Manager.cs
index 900688a8..96a9087b 100644
--- a/Assets/SteamVR/Input/SteamVR_ActionSet_Manager.cs
+++ b/Assets/SteamVR/Input/SteamVR_ActionSet_Manager.cs
@@ -74,12 +74,20 @@ public static void SetChanged()
             changed = true;
         }
 
+        private static Dictionary<int, VRActiveActionSet_t[]> pool;
+        private static VRActiveActionSet_t[] activeActionSetsArray;
+
         private static void UpdateActionSetsArray()
         {
-            List<VRActiveActionSet_t> activeActionSetsList = new List<VRActiveActionSet_t>();
-
+            var activeActionSetsCount = 0;
             SteamVR_Input_Sources[] sources = SteamVR_Input_Source.GetAllSources();
 
+            if (pool == null)
+            {
+                pool = new Dictionary<int, VRActiveActionSet_t[]>();
+                activeActionSetsArray = new VRActiveActionSet_t[SteamVR_Input.actionSets.Length * sources.Length];
+            }
+
             for (int actionSetIndex = 0; actionSetIndex < SteamVR_Input.actionSets.Length; actionSetIndex++)
             {
                 SteamVR_ActionSet set = SteamVR_Input.actionSets[actionSetIndex];
@@ -95,20 +103,44 @@ private static void UpdateActionSetsArray()
                         activeSet.nPriority = set.ReadRawSetPriority(source);
                         activeSet.ulRestrictedToDevice = SteamVR_Input_Source.GetHandle(source);
 
-                        int insertionIndex = 0;
-                        for (insertionIndex = 0; insertionIndex < activeActionSetsList.Count; insertionIndex++)
+                        int insertionIndex;
+                        for (insertionIndex = 0; insertionIndex < activeActionSetsCount; insertionIndex++)
                         {
-                            if (activeActionSetsList[insertionIndex].nPriority > activeSet.nPriority)
+                            if (activeActionSetsArray[insertionIndex].nPriority > activeSet.nPriority)
                                 break;
                         }
-                        activeActionSetsList.Insert(insertionIndex, activeSet);
+
+                        for (int i = activeActionSetsCount; i > insertionIndex; i--)
+                        {
+                            activeActionSetsArray[i] = activeActionSetsArray[i - 1];
+                        }
+                        activeActionSetsArray[insertionIndex] = activeSet;
+                        activeActionSetsCount++;
                     }
                 }
             }
 
+            if (rawActiveActionSetArray != null && rawActiveActionSetArray.Length != activeActionSetsCount)
+            {
+                pool[rawActiveActionSetArray.Length] = rawActiveActionSetArray;
+                rawActiveActionSetArray = null;
+            }
+
+            if (rawActiveActionSetArray == null)
+            {
+                if (!pool.ContainsKey(activeActionSetsCount))
+                {
+                    rawActiveActionSetArray = new VRActiveActionSet_t[activeActionSetsCount];
+                    pool[activeActionSetsCount] = rawActiveActionSetArray;
+                }
+                else
+                    rawActiveActionSetArray = pool[activeActionSetsCount];
+            }
+
             changed = false;
 
-            rawActiveActionSetArray = activeActionSetsList.ToArray();
+            for (int i = 0; i < activeActionSetsCount; i++)
+                rawActiveActionSetArray[i] = activeActionSetsArray[i];
 
             if (Application.isEditor || updateDebugTextInBuilds)
                 UpdateDebugText();
diff --git a/Assets/SteamVR/Scripts/SteamVR.cs b/Assets/SteamVR/Scripts/SteamVR.cs
index f80dc407..b6d5e7bd 100644
--- a/Assets/SteamVR/Scripts/SteamVR.cs
+++ b/Assets/SteamVR/Scripts/SteamVR.cs
@@ -26,12 +26,14 @@ public class SteamVR : System.IDisposable
 
         // Set this to false to keep from auto-initializing when calling SteamVR.instance.
         private static bool _enabled = true;
+        private static readonly string[] SupportedDevices = XRSettings.supportedDevices;
+
         public static bool enabled
         {
             get
             {
 #if UNITY_2020_1_OR_NEWER || OPENVR_XR_API
-                if (XRSettings.supportedDevices.Length == 0)
+                if (SupportedDevices.Length == 0)
                     enabled = false;
 #else
                 if (!XRSettings.enabled)
@@ -127,11 +129,11 @@ private static void ReportGeneralErrors()
 
             if (XRSettings.enabled == false)
                 errorLog += "VR may be disabled in player settings. Go to player settings in the editor and check the 'Virtual Reality Supported' checkbox'. ";
-            if (XRSettings.supportedDevices != null && XRSettings.supportedDevices.Length > 0)
+            if (SupportedDevices != null && SupportedDevices.Length > 0)
             {
-                if (XRSettings.supportedDevices.Contains("OpenVR") == false)
+                if (SupportedDevices.Contains("OpenVR") == false)
                     errorLog += "OpenVR is not in your list of supported virtual reality SDKs. Add it to the list in player settings. ";
-                else if (XRSettings.supportedDevices.First().Contains("OpenVR") == false)
+                else if (SupportedDevices.First().Contains("OpenVR") == false)
                     errorLog += "OpenVR is not first in your list of supported virtual reality SDKs. <b>This is okay, but if you have an Oculus device plugged in, and Oculus above OpenVR in this list, it will try and use the Oculus SDK instead of OpenVR.</b> ";
             }
             else