diff --git a/comfy/model_management.py b/comfy/model_management.py
index 79c0dfdb4..0d040e55e 100644
--- a/comfy/model_management.py
+++ b/comfy/model_management.py
@@ -1082,8 +1082,20 @@ def cast_to_device(tensor, device, dtype, copy=False):
     non_blocking = device_supports_non_blocking(device)
     return cast_to(tensor, dtype=dtype, device=device, non_blocking=non_blocking, copy=copy)
 
+
+PINNED_MEMORY = {}
+TOTAL_PINNED_MEMORY = 0
+if PerformanceFeature.PinnedMem in args.fast:
+    if WINDOWS:
+        MAX_PINNED_MEMORY = get_total_memory(torch.device("cpu")) * 0.45  # Windows limit is apparently 50%
+    else:
+        MAX_PINNED_MEMORY = get_total_memory(torch.device("cpu")) * 0.95
+else:
+    MAX_PINNED_MEMORY = -1
+
 def pin_memory(tensor):
-    if PerformanceFeature.PinnedMem not in args.fast:
+    global TOTAL_PINNED_MEMORY
+    if MAX_PINNED_MEMORY <= 0:
         return False
 
     if not is_nvidia():
@@ -1092,13 +1104,21 @@ def pin_memory(tensor):
     if not is_device_cpu(tensor.device):
         return False
 
-    if torch.cuda.cudart().cudaHostRegister(tensor.data_ptr(), tensor.numel() * tensor.element_size(), 1) == 0:
+    size = tensor.numel() * tensor.element_size()
+    if (TOTAL_PINNED_MEMORY + size) > MAX_PINNED_MEMORY:
+        return False
+
+    ptr = tensor.data_ptr()
+    if torch.cuda.cudart().cudaHostRegister(ptr, size, 1) == 0:
+        PINNED_MEMORY[ptr] = size
+        TOTAL_PINNED_MEMORY += size
         return True
 
     return False
 
 def unpin_memory(tensor):
-    if PerformanceFeature.PinnedMem not in args.fast:
+    global TOTAL_PINNED_MEMORY
+    if MAX_PINNED_MEMORY <= 0:
         return False
 
     if not is_nvidia():
@@ -1107,7 +1127,11 @@ def unpin_memory(tensor):
     if not is_device_cpu(tensor.device):
         return False
 
-    if torch.cuda.cudart().cudaHostUnregister(tensor.data_ptr()) == 0:
+    ptr = tensor.data_ptr()
+    if torch.cuda.cudart().cudaHostUnregister(ptr) == 0:
+        TOTAL_PINNED_MEMORY -= PINNED_MEMORY.pop(ptr)
+        if len(PINNED_MEMORY) == 0:
+            TOTAL_PINNED_MEMORY = 0
         return True
 
     return False
diff --git a/comfy_execution/caching.py b/comfy_execution/caching.py
index e077f78b0..326a279fc 100644
--- a/comfy_execution/caching.py
+++ b/comfy_execution/caching.py
@@ -399,6 +399,8 @@ class RAMPressureCache(LRUCache):
             ram_usage = RAM_CACHE_DEFAULT_RAM_USAGE
             def scan_list_for_ram_usage(outputs):
                 nonlocal ram_usage
+                if outputs is None:
+                    return
                 for output in outputs:
                     if isinstance(output, list):
                         scan_list_for_ram_usage(output)
diff --git a/requirements.txt b/requirements.txt
index d275653b1..acf969977 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 comfyui-frontend-package==1.28.8
-comfyui-workflow-templates==0.2.4
+comfyui-workflow-templates==0.2.11
 comfyui-embedded-docs==0.3.1
 comfyui_manager==4.0.3b1
 torch