Comfy-Org/ComfyUI · error · RuntimeError

Cannot create non-dynamic delegate: cached_patcher_init is n

Error message

Cannot create non-dynamic delegate: cached_patcher_init is not initialized.

What it means

Cloning a dynamic ModelPatcher into a non-dynamic delegate requires re-instantiating the model through the loader factory stored in cached_patcher_init. If that factory was never registered (custom loader bypassed the core loader plumbing), the clone path has no way to rebuild a clean model and raises RuntimeError rather than producing a half-configured delegate.

Source

Thrown at comfy/model_patcher.py:437

        #the vast majority of setups a little bit of offloading on the giant model more
        #than pays for CFG. So return everything both torch and Aimdo could give us
        aimdo_mem = 0
        if comfy.memory_management.aimdo_enabled:
            aimdo_device = device.index if getattr(device, "type", None) == "cuda" else None
            aimdo_mem = comfy_aimdo.model_vbar.vbars_analyze(aimdo_device)
        return comfy.model_management.get_free_memory(device) + aimdo_mem

    def get_clone_model_override(self):
        return self.model, (self.backup, self.backup_buffers, self.object_patches_backup, self.pinned)

    def clone(self, disable_dynamic=False, model_override=None, force_deepcopy=False):
        class_ = self.__class__
        if self.is_dynamic() and disable_dynamic or force_deepcopy:
            if self.is_dynamic() and disable_dynamic:
                class_ = ModelPatcher
            if model_override is None:
                if self.cached_patcher_init is None:
                    raise RuntimeError("Cannot create non-dynamic delegate: cached_patcher_init is not initialized.")
                temp_model_patcher = self.cached_patcher_init[0](*self.cached_patcher_init[1], disable_dynamic=True)
                if len(self.cached_patcher_init) > 2:
                    temp_model_patcher = temp_model_patcher[self.cached_patcher_init[2]]
                model_override = temp_model_patcher.get_clone_model_override()
        if model_override is None:
            model_override = self.get_clone_model_override()

        n = class_(model_override[0], self.load_device, self.offload_device, self.model_size(), weight_inplace_update=self.weight_inplace_update)
        n.patches = {}
        for k in self.patches:
            n.patches[k] = self.patches[k][:]
        n.patches_uuid = self.patches_uuid

        n.object_patches = self.object_patches.copy()
        n.weight_wrapper_patches = self.weight_wrapper_patches.copy()
        n.model_options = comfy.utils.deepcopy_list_dict(self.model_options)
        n.parent = self

View on GitHub (pinned to 1c6d8d45b3)

Solutions

Load the model with a core loader (CheckpointLoaderSimple, UNETLoader, CLIPLoader/DualCLIPLoader, VAELoader) so cached_patcher_init is registered.
If you maintain the custom loader, register a cached_patcher_init factory that rebuilds the patcher from the checkpoint.
As a user, drop --fast startup arguments when working with models from custom loaders.

Defensive patterns

Strategy: validation

Validate before calling

patcher = loader_output
if getattr(patcher, "is_dynamic", lambda: False)() and patcher.cached_patcher_init is None:
    raise RuntimeError("custom loader did not register cached_patcher_init; cannot make non-dynamic clone")
clone = patcher.clone(disable_dynamic=True)

Type guard

def supports_dynamic_delegate(patcher) -> bool:
    return (not patcher.is_dynamic()) or patcher.cached_patcher_init is not None

Prevention

Prefer core loaders for models that will be cloned or used with hooks.
Custom loader authors: register cached_patcher_init when constructing the ModelPatcher.
Avoid --fast when mixing custom loaders into the workflow.

When it happens

Trigger: patcher.clone(disable_dynamic=True) or clone(force_deepcopy=True) on a ModelPatcher whose cached_patcher_init is None — typically a patcher returned by a custom node loader that constructed ModelPatcher directly.

Common situations: Using --fast (dynamic patcher) together with a custom-node model loader; nodes that call clone(disable_dynamic=True) for hooks or sampling on models from non-core loaders; older custom loaders not updated for the cached_patcher_init contract.

Related errors

AI-assisted analysis of Comfy-Org/ComfyUI@1c6d8d45b3 (2026-08-14). Data as JSON: /api/errors/45f6e344d0149906. Report an issue: GitHub.