Handle CPU torch more gracefully

comfy/model_management.py

@@ -1,8 +1,8 @@
 from __future__ import annotations
 
 import logging
-import sys
 import platform
+import sys
 import warnings
 from enum import Enum
 from threading import RLock
@@ -49,7 +49,7 @@ if args.deterministic:
 
 directml_device = None
 if args.directml is not None:
-    import torch_directml # pylint: disable=import-error
+    import torch_directml  # pylint: disable=import-error
 
     device_index = args.directml
     if device_index < 0:
@@ -61,7 +61,7 @@ if args.directml is not None:
     lowvram_available = False  # TODO: need to find a way to get free memory in directml before this can be enabled by default.
 
 try:
-    import intel_extension_for_pytorch as ipex # pylint: disable=import-error
+    import intel_extension_for_pytorch as ipex  # pylint: disable=import-error
 
     if torch.xpu.is_available():
         xpu_available = True
@@ -158,8 +158,8 @@ if args.disable_xformers:
     XFORMERS_IS_AVAILABLE = False
 else:
     try:
-        import xformers # pylint: disable=import-error
-        import xformers.ops # pylint: disable=import-error
+        import xformers  # pylint: disable=import-error
+        import xformers.ops  # pylint: disable=import-error
 
         XFORMERS_IS_AVAILABLE = True
         try:
@@ -186,6 +186,7 @@ def is_nvidia():
             return True
     return False
 
+
 def is_amd():
     global cpu_state
     if cpu_state == CPUState.GPU:
@@ -193,6 +194,7 @@ def is_amd():
             return True
     return False
 
+
 ENABLE_PYTORCH_ATTENTION = False
 if args.use_pytorch_cross_attention:
     ENABLE_PYTORCH_ATTENTION = True
@@ -287,7 +289,6 @@ try:
 except:
     logging.warning("Could not pick default device.")
 
-
 current_loaded_models: List["LoadedModel"] = []
 
 
@@ -506,6 +507,7 @@ def load_model_gpu(model):
     with model_management_lock:
         return load_models_gpu([model])
 
+
 def loaded_models(only_currently_used=False):
     with model_management_lock:
         output = []
@@ -517,6 +519,7 @@ def loaded_models(only_currently_used=False):
             output.append(m.model)
         return output
 
+
 def cleanup_models(keep_clone_weights_loaded=False):
     with model_management_lock:
         to_delete = []
@@ -704,14 +707,15 @@ def supports_dtype(device, dtype):  # TODO
         return True
     return False
 
-def supports_cast(device, dtype): #TODO
+
+def supports_cast(device, dtype):  # TODO
     if dtype == torch.float32:
         return True
     if dtype == torch.float16:
         return True
     if is_device_mps(device):
         return False
-    if directml_device: #TODO: test this
+    if directml_device:  # TODO: test this
         return False
     if dtype == torch.bfloat16:
         return True
@@ -721,28 +725,31 @@ def supports_cast(device, dtype): #TODO
         return True
     return False
 
+
 def device_supports_non_blocking(device):
     if is_device_mps(device):
         return False  # pytorch bug? mps doesn't support non blocking
     if is_intel_xpu():
         return False
-    if args.deterministic: #TODO: figure out why deterministic breaks non blocking from gpu to cpu (previews)
+    if args.deterministic:  # TODO: figure out why deterministic breaks non blocking from gpu to cpu (previews)
         return False
     if directml_device:
         return False
     return True
 
+
 def device_should_use_non_blocking(device):
     if not device_supports_non_blocking(device):
         return False
     return False
     # return True #TODO: figure out why this causes memory issues on Nvidia and possibly others
 
+
 def force_channels_last():
     if args.force_channels_last:
         return True
 
-    #TODO
+    # TODO
     return False
 
 
@@ -805,10 +812,11 @@ def pytorch_attention_flash_attention():
             return True
     return False
 
+
 def force_upcast_attention_dtype():
     upcast = args.force_upcast_attention
     try:
-        if platform.mac_ver()[0] in ['14.5']: #black image bug on OSX Sonoma 14.5
+        if platform.mac_ver()[0] in ['14.5']:  # black image bug on OSX Sonoma 14.5
             upcast = True
     except:
         pass
@@ -817,6 +825,7 @@ def force_upcast_attention_dtype():
     else:
         return None
 
+
 def get_free_memory(dev=None, torch_free_too=False):
     global directml_device
     if dev is None:
@@ -906,12 +915,15 @@ def should_use_fp16(device=None, model_params=0, prioritize_performance=True, ma
 
     if is_amd():
         return True
+    try:
+        props = torch.cuda.get_device_properties("cuda")
+        if props.major >= 8:
+            return True
 
-    props = torch.cuda.get_device_properties("cuda")
-    if props.major >= 8:
-        return True
-
-    if props.major < 6:
+        if props.major < 6:
+            return False
+    except AssertionError:
+        logging.warning("Torch was not compiled with cuda support")
         return False
 
     fp16_works = False
@@ -967,9 +979,13 @@ def should_use_bf16(device=None, model_params=0, prioritize_performance=True, ma
     if device is None:
         device = torch.device("cuda")
 
-    props = torch.cuda.get_device_properties(device)
-    if props.major >= 8:
-        return True
+    try:
+        props = torch.cuda.get_device_properties(device)
+        if props.major >= 8:
+            return True
+    except AssertionError:
+        logging.warning("Torch was not compiled with CUDA support")
+        return False
 
     bf16_works = torch.cuda.is_bf16_supported()