actual solution to the uncommon hanging problem that is seemingly caused by multiple progress requests working on same tensor

modules/progress.py

@@ -95,31 +95,30 @@ def progressapi(req: ProgressRequest):
     predicted_duration = elapsed_since_start / progress if progress > 0 else None
     eta = predicted_duration - elapsed_since_start if predicted_duration is not None else None
 
+    live_preview = None
     id_live_preview = req.id_live_preview
-    shared.state.set_current_image()
-    if opts.live_previews_enable and req.live_preview and shared.state.id_live_preview != req.id_live_preview:
-        image = shared.state.current_image
-        if image is not None:
-            buffered = io.BytesIO()
 
-            if opts.live_previews_image_format == "png":
+    if opts.live_previews_enable and req.live_preview:
-                # using optimize for large images takes an enormous amount of time
+        shared.state.set_current_image()
-                if max(*image.size) <= 256:
+        if shared.state.id_live_preview != req.id_live_preview:
-                    save_kwargs = {"optimize": True}
+            image = shared.state.current_image
+            if image is not None:
+                buffered = io.BytesIO()
+
+                if opts.live_previews_image_format == "png":
+                    # using optimize for large images takes an enormous amount of time
+                    if max(*image.size) <= 256:
+                        save_kwargs = {"optimize": True}
+                    else:
+                        save_kwargs = {"optimize": False, "compress_level": 1}
+
                 else:
-                    save_kwargs = {"optimize": False, "compress_level": 1}
+                    save_kwargs = {}
 
-            else:
+                image.save(buffered, format=opts.live_previews_image_format, **save_kwargs)
-                save_kwargs = {}
+                base64_image = base64.b64encode(buffered.getvalue()).decode('ascii')
-
+                live_preview = f"data:image/{opts.live_previews_image_format};base64,{base64_image}"
-            image.save(buffered, format=opts.live_previews_image_format, **save_kwargs)
+                id_live_preview = shared.state.id_live_preview
-            base64_image = base64.b64encode(buffered.getvalue()).decode('ascii')
-            live_preview = f"data:image/{opts.live_previews_image_format};base64,{base64_image}"
-            id_live_preview = shared.state.id_live_preview
-        else:
-            live_preview = None
-    else:
-        live_preview = None
 
     return ProgressResponse(active=active, queued=queued, completed=completed, progress=progress, eta=eta, live_preview=live_preview, id_live_preview=id_live_preview, textinfo=shared.state.textinfo)
 

modules/sd_samplers_common.py

@@ -111,7 +111,7 @@ def images_tensor_to_samples(image, approximation=None, model=None):
 
 
 def store_latent(decoded):
-    state.current_latent = decoded.clone()
+    state.current_latent = decoded
 
     if opts.live_previews_enable and opts.show_progress_every_n_steps > 0 and shared.state.sampling_step % opts.show_progress_every_n_steps == 0:
         if not shared.parallel_processing_allowed:

modules/shared_state.py

@@ -128,7 +128,7 @@ class State:
         devices.torch_gc()
 
     def set_current_image(self):
-        """sets self.current_image from self.current_latent if enough sampling steps have been made after the last call to this"""
+        """if enough sampling steps have been made after the last call to this, sets self.current_image from self.current_latent, and modifies self.id_live_preview accordingly"""
         if not shared.parallel_processing_allowed:
             return