Allow different models to estimate memory usage differently.

comfy/model_base.py

@@ -157,6 +157,16 @@ class BaseModel(torch.nn.Module):
     def set_inpaint(self):
         self.inpaint_model = True
 
+    def memory_required(self, input_shape):
+        area = input_shape[0] * input_shape[2] * input_shape[3]
+        if comfy.model_management.xformers_enabled() or comfy.model_management.pytorch_attention_flash_attention():
+            #TODO: this needs to be tweaked
+            return (area / 20) * (1024 * 1024)
+        else:
+            #TODO: this formula might be too aggressive since I tweaked the sub-quad and split algorithms to use less memory.
+            return (((area * 0.6) / 0.9) + 1024) * (1024 * 1024)
+
+
 def unclip_adm(unclip_conditioning, device, noise_augmentor, noise_augment_merge=0.0):
     adm_inputs = []
     weights = []