Hqq serialization (#33141)

* HQQ model serialization attempt

* fix hqq dispatch and unexpected keys

* style

* remove check_old_param

* revert to check HQQLinear in quantizer_hqq.py

* revert to check HQQLinear in quantizer_hqq.py

* update HqqConfig default params

* make ci happy

* make ci happy

* revert to HQQLinear check in quantizer_hqq.py

* check hqq_min version 0.2.0

* set axis=1 as default in quantization_config.py

* validate_env with hqq>=0.2.0 version message

* deprecated hqq kwargs message

* make ci happy

* remove run_expected_keys_check hack + bump to 0.2.1 min hqq version

* fix unexpected_keys hqq update

* add pre_quantized check

* add update_expected_keys to base quantizerr

* ci base.py fix?

* ci base.py fix?

* fix "quantization typo" src/transformers/utils/quantization_config.py

Co-authored-by: Arthur <48595927+ArthurZucker@users.noreply.github.com>

* fix post merge

---------

Co-authored-by: Marc Sun <marc@huggingface.co>
Co-authored-by: Arthur <48595927+ArthurZucker@users.noreply.github.com>

docs/source/en/quantization/hqq.md

@@ -30,13 +30,13 @@ To quantize a model, you need to create an [`HqqConfig`]. There are two ways of
 from transformers import AutoModelForCausalLM, AutoTokenizer, HqqConfig
 
 # Method 1: all linear layers will use the same quantization config
-quant_config  = HqqConfig(nbits=8, group_size=64, quant_zero=False, quant_scale=False, axis=0) #axis=0 is used by default
+quant_config  = HqqConfig(nbits=8, group_size=64)
 ```
 
 ``` Python
 # Method 2: each linear layer with the same tag will use a dedicated quantization config
-q4_config = {'nbits':4, 'group_size':64, 'quant_zero':False, 'quant_scale':False}
-q3_config = {'nbits':3, 'group_size':32, 'quant_zero':False, 'quant_scale':False}
+q4_config = {'nbits':4, 'group_size':64}
+q3_config = {'nbits':3, 'group_size':32}
 quant_config  = HqqConfig(dynamic_config={
   'self_attn.q_proj':q4_config,
   'self_attn.k_proj':q4_config,

src/transformers/integrations/hqq.py

@@ -66,6 +66,10 @@ def _prepare_for_hqq_linear(model, patch_params, has_been_replaced, current_key_
 
             has_been_replaced = True
 
+            # Add these fake parameters to avoid loading fail
+            for att in ["W_q", "meta"]:
+                setattr(module, att, None)
+
         if len(list(module.children())) > 0:
             _, has_been_replaced = _prepare_for_hqq_linear(
                 module,
@@ -97,7 +101,7 @@ def prepare_for_hqq_linear(model, quantization_config=None, modules_to_not_conve
 
     # Convert quantization_config to layer-wise config
     skip_modules = quantization_config.skip_modules
-    quant_config = quantization_config.to_dict()
+    quant_config = quantization_config.quant_config
     linear_tags = list(set(linear_tags) - set(skip_modules) - set(modules_to_not_convert))
 
     if any(key in linear_tags for key in quant_config.keys()):
@@ -113,7 +117,11 @@ def prepare_for_hqq_linear(model, quantization_config=None, modules_to_not_conve
     )
 
     # We store quantization config as linear_tag -> hqq quant config
-    model.config.quantization_config = patch_params
+    model.config.quantization_config = {
+        "quant_config": quant_config,
+        "quant_method": quantization_config.quant_method,
+        "skip_modules": skip_modules,
+    }
 
     if not has_been_replaced:
         logger.warning("No linear modules were found in your model for quantization.")

src/transformers/modeling_utils.py

@@ -934,12 +934,17 @@ def _load_state_dict_into_meta_model(
         # For compatibility with PyTorch load_state_dict which converts state dict dtype to existing dtype in model, and which
         # uses `param.copy_(input_param)` that preserves the contiguity of the parameter in the model.
         # Reference: https://github.com/pytorch/pytorch/blob/db79ceb110f6646523019a59bbd7b838f43d4a86/torch/nn/modules/module.py#L2040C29-L2040C29
+
         old_param = model
         splits = param_name.split(".")
         for split in splits:
             old_param = getattr(old_param, split)
+            # Not all the attributes of a module are Parameters/Tensor
+            if not isinstance(old_param, (torch.nn.Parameter, torch.Tensor)):
+                old_param = None
             if old_param is None:
                 break
+
         if old_param is not None:
             if dtype is None:
                 param = param.to(old_param.dtype)
@@ -3819,6 +3824,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin, GenerationMixin, PushToHubMix
         from_pt = not (from_tf | from_flax)
 
         # load pt weights early so that we know which dtype to init the model under
+
         if from_pt:
             if not is_sharded and state_dict is None:
                 # Time to load the checkpoint
@@ -4176,6 +4182,9 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin, GenerationMixin, PushToHubMix
         expected_keys = list(model_state_dict.keys())
         prefix = model.base_model_prefix
 
+        if hf_quantizer is not None:
+            expected_keys = hf_quantizer.update_expected_keys(model, expected_keys, loaded_keys)
+
         def _fix_key(key):
             if "beta" in key:
                 return key.replace("beta", "bias")
@@ -4290,7 +4299,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin, GenerationMixin, PushToHubMix
                     value = torch.empty(*param.size(), dtype=target_dtype)
                     if (
                         not is_quantized
-                        or getattr(hf_quantizer, "requires_parameters_quantization", False)
+                        or (getattr(hf_quantizer, "requires_parameters_quantization", False))
                         or not hf_quantizer.check_quantized_param(
                             model, param_value=value, param_name=key, state_dict={}
                         )

src/transformers/quantizers/base.py

@@ -109,6 +109,18 @@ class HfQuantizer(ABC):
         """
         return missing_keys
 
+    def update_expected_keys(self, model, expected_keys: List[str], loaded_keys: List[str]) -> List[str]:
+        """
+        Override this method if you want to adjust the `update_expected_keys`.
+
+        Args:
+            expected_keys (`List[str]`, *optional*):
+                The list of the expected keys in the initialized model.
+            loaded_keys (`List[str]`, *optional*):
+                The list of the loaded keys in the checkpoint.
+        """
+        return expected_keys
+
     def get_special_dtypes_update(self, model, torch_dtype: "torch.dtype") -> Dict[str, "torch.dtype"]:
         """
         returns dtypes for modules that are not quantized - used for the computation of the device_map in case

src/transformers/quantizers/quantizer_hqq.py

@@ -62,7 +62,7 @@ class HqqHfQuantizer(HfQuantizer):
     def validate_environment(self, *args, **kwargs):
         if not (is_hqq_available()):
             raise ImportError(
-                "HQQ is not available. Please follow the instructions to install it: `https://github.com/mobiusml/hqq/`"
+                "A valid HQQ version (>=0.2.1) is not available. Please follow the instructions to install it: `https://github.com/mobiusml/hqq/`."
             )
 
         if kwargs.get("from_tf", False) or kwargs.get("from_flax", False):
@@ -91,6 +91,65 @@ class HqqHfQuantizer(HfQuantizer):
             else:
                 self.using_multi_gpu = len(set(device_map.values())) > 1
 
+    def update_missing_keys(
+        self, model: "PreTrainedModel", missing_keys: List[str], prefix: str, **kwargs
+    ) -> List[str]:
+        if self.pre_quantized:
+            return [key for key in missing_keys if ("weight" not in key)]
+        else:
+            return missing_keys
+
+    # Adds missing keys for HQQLinear modules that are loaded but the model with initialized with torch.nn.Linear
+    def update_expected_keys(
+        self, model: "PreTrainedModel", expected_keys: List[str], loaded_keys: List[str]
+    ) -> List[str]:
+        if not self.pre_quantized:
+            return expected_keys
+
+        # Collects all quantizable (linear) layers
+        def _find_hqq_quantizable_layers(model, layers):
+            for name, module in model.named_children():
+                if isinstance(module, (torch.nn.Linear)):
+                    layers.add(module.name)
+                _find_hqq_quantizable_layers(module, layers)
+
+        new_keys = set(expected_keys)
+        if is_hqq_available():
+            from hqq.core.quantize import HQQLinear
+
+            # Name modules
+            for name, module in model.named_modules():
+                module.name = name
+
+            # valid modules are Linear layers that have HQQLinear state_dict. We ignore skip_modules and any layers with Linear state_dict() params
+            _valid_modules = set()
+            _find_hqq_quantizable_layers(model, _valid_modules)
+            _valid_modules -= set(model.config.quantization_config["skip_modules"])
+
+            # Append new expected layers based on _ref_keys
+            _ref_keys = HQQLinear(
+                linear_layer=None, quant_config=None, compute_dtype=torch.float16, device="cpu"
+            ).state_dict_keys() - {"bias"}
+
+            # Clean-up
+            _rm_keys = set()
+            for key in new_keys:
+                if any(_module in key for _module in _valid_modules):
+                    _rm_keys.add(key)
+            new_keys -= _rm_keys
+            # At this point, new_keys contains all the keys of the layers that are NOT HQQLinear or torch.nn.Linear
+
+            # Re-populate Linear/HQQLinear
+            for _module in _valid_modules:
+                if _module + ".weight" in loaded_keys:
+                    new_keys.add(_module + ".weight")
+                else:
+                    new_keys.update({_module + "." + _ref_key for _ref_key in _ref_keys})
+                if _module + ".bias" in loaded_keys:
+                    new_keys.add(_module + ".bias")
+
+        return list(new_keys)
+
     def check_quantized_param(
         self,
         model: "PreTrainedModel",
@@ -99,9 +158,18 @@ class HqqHfQuantizer(HfQuantizer):
         state_dict: Dict[str, Any],
         **kwargs,
     ) -> bool:
+        if is_hqq_available():
+            from hqq.core.quantize import HQQLinear
         module, tensor_name = get_module_from_name(model, param_name)
 
-        return isinstance(module, torch.nn.Linear) and (tensor_name == "weight")
+        if self.pre_quantized:
+            return (
+                (isinstance(module, torch.nn.Linear) or isinstance(module, HQQLinear))
+                and tensor_name != "weight"
+                and tensor_name != "bias"
+            )
+        else:
+            return isinstance(module, torch.nn.Linear) and tensor_name == "weight"
 
     def create_quantized_param(
         self,
@@ -122,13 +190,43 @@ class HqqHfQuantizer(HfQuantizer):
             from hqq.core.quantize import HQQLinear
 
         module, tensor_name = get_module_from_name(model, param_name)
-
-        layer_name = param_name.replace(".weight", "").replace(".bias", "")
+        layer_name = ".".join(param_name.split(".")[:-1])
         parent_module = find_parent(model, layer_name)
         node = layer_name.split(".")[-1]
 
-        # Step 0: set module state_dict
-        module_state_dict = {key.split(".")[-1]: state_dict[key] for key in state_dict if layer_name in key}
+        # set module state_dict
+        module_state_dict = {}
+        for k, v in state_dict.items():
+            if layer_name + "." in k:
+                module_state_dict[k.split(".")[-1]] = v
+                if unexpected_keys is not None and k in unexpected_keys:
+                    unexpected_keys.remove(k)
+
+        if self.pre_quantized:
+            if isinstance(module, HQQLinear):
+                return
+            else:
+                hqq_layer = HQQLinear(
+                    linear_layer=None,
+                    quant_config=None,
+                    compute_dtype=self.torch_dtype,
+                    device=target_device,
+                )
+
+            hqq_layer.load_state_dict(module_state_dict)
+
+            if hqq_layer.bias is not None and isinstance(hqq_layer.bias, torch.Tensor):
+                hqq_layer.bias = torch.nn.Parameter(hqq_layer.bias)
+
+            if self.using_multi_gpu:
+                hqq_layer = self._patch_layer_for_multigpu(hqq_layer)
+
+            setattr(parent_module, node, hqq_layer)
+
+            # cleanup
+            del module.__dict__, module
+            torch.cuda.empty_cache()
+            return
 
         # Step 1: populate module with weight/bias from module state dict
         for key in module_state_dict:
@@ -136,7 +234,6 @@ class HqqHfQuantizer(HfQuantizer):
 
         # Step 2: Replace module with either HQQLinear or move it to device. We do this via setattr on the parent as doing on it on the module
         # directly doesn't work.
-
         if hasattr(module, "quant_config"):
             hqq_layer = HQQLinear(
                 module,
@@ -192,7 +289,7 @@ class HqqHfQuantizer(HfQuantizer):
         return model
 
     def is_serializable(self, safe_serialization=None):
-        return False
+        return True
 
     @property
     def is_trainable(self) -> bool:

src/transformers/utils/import_utils.py

@@ -92,6 +92,7 @@ ACCELERATE_MIN_VERSION = "0.26.0"
 FSDP_MIN_VERSION = "1.12.0"
 GGUF_MIN_VERSION = "0.10.0"
 XLA_FSDPV2_MIN_VERSION = "2.2.0"
+HQQ_MIN_VERSION = "0.2.1"
 
 
 _accelerate_available, _accelerate_version = _is_package_available("accelerate", return_version=True)
@@ -181,7 +182,7 @@ _torchao_available = _is_package_available("torchao")
 _torchdistx_available = _is_package_available("torchdistx")
 _torchvision_available = _is_package_available("torchvision")
 _mlx_available = _is_package_available("mlx")
-_hqq_available = _is_package_available("hqq")
+_hqq_available, _hqq_version = _is_package_available("hqq", return_version=True)
 _tiktoken_available = _is_package_available("tiktoken")
 _blobfile_available = _is_package_available("blobfile")
 _liger_kernel_available = _is_package_available("liger_kernel")
@@ -323,8 +324,8 @@ def is_torch_deterministic():
         return True
 
 
-def is_hqq_available():
-    return _hqq_available
+def is_hqq_available(min_version: str = HQQ_MIN_VERSION):
+    return _hqq_available and version.parse(_hqq_version) >= version.parse(min_version)
 
 
 def is_pygments_available():

src/transformers/utils/quantization_config.py

@@ -193,15 +193,9 @@ class HqqConfig(QuantizationConfigMixin):
             Number of bits. Supported values are (8, 4, 3, 2, 1).
         group_size (`int`, *optional*, defaults to 64):
             Group-size value. Supported values are any value that is divisble by weight.shape[axis]).
-        quant_zero (`bool`, *optional*, defaults to `True`):
-            Quantize the zero-point if set to `True`.
-        quant_scale (`bool`, *optional*, defaults to `False`):
-            Quantize the scaling if set to `True`.
-        offload_meta (`bool`, *optional*, defaults to `False`):
-            Offload the meta-data to the CPU if set to `True`.
         view_as_float (`bool`, *optional*, defaults to `False`):
             View the quantized weight as float (used in distributed training) if set to `True`.
-        axis (`int`, *optional*, defaults to 0):
+        axis (`Optional[int]`, *optional*):
             Axis along which grouping is performed. Supported values are 0 or 1.
         dynamic_config (dict, *optional*):
             Parameters for dynamic configuration. The key is the name tag of the layer and the value is a quantization config.
@@ -216,11 +210,8 @@ class HqqConfig(QuantizationConfigMixin):
         self,
         nbits: int = 4,
         group_size: int = 64,
-        quant_zero: bool = True,
-        quant_scale: bool = False,
-        offload_meta: bool = False,
         view_as_float: bool = False,
-        axis: int = 0,
+        axis: Optional[int] = None,
         dynamic_config: Optional[dict] = None,
         skip_modules: List[str] = ["lm_head"],
         **kwargs,
@@ -228,6 +219,16 @@ class HqqConfig(QuantizationConfigMixin):
         if is_hqq_available():
             from hqq.core.quantize import BaseQuantizeConfig as HQQBaseQuantizeConfig
 
+        for deprecated_key in ["quant_zero", "quant_scale", "offload_meta"]:
+            if deprecated_key in kwargs:
+                logger.info(
+                    deprecated_key + " is deprecated. This parameter will be ignored in quantization settings."
+                )
+
+        if axis is None:
+            axis = 1
+            logger.info("Setting axis=1 as faster backends such as TorchAO or BitBlas are only compatible with it.")
+
         if axis not in [0, 1]:
             raise ValueError("Invalid axis value. Only 0 and 1 are allowed.")
 
@@ -240,9 +241,6 @@ class HqqConfig(QuantizationConfigMixin):
                 **{
                     "nbits": nbits,
                     "group_size": group_size,
-                    "quant_zero": quant_zero,
-                    "quant_scale": quant_scale,
-                    "offload_meta": offload_meta,
                     "view_as_float": view_as_float,
                     "axis": axis,
                 }
@@ -259,12 +257,26 @@ class HqqConfig(QuantizationConfigMixin):
         """
         pass
 
+    @classmethod
+    def from_dict(cls, config: Dict[str, Any]):
+        """
+        Override from_dict, used in AutoQuantizationConfig.from_dict in quantizers/auto.py
+        """
+        instance = cls()
+        instance.quant_config = config["quant_config"]
+        instance.skip_modules = config["skip_modules"]
+        return instance
+
     def to_dict(self) -> Dict[str, Any]:
         """
         Serializes this instance to a Python dictionary. Returns:
             `Dict[str, Any]`: Dictionary of all the attributes that make up this configuration instance.
         """
-        return self.quant_config
+        return {
+            "quant_config": self.quant_config,
+            "quant_method": self.quant_method,
+            "skip_modules": self.skip_modules,
+        }
 
     def __repr__(self):
         config_dict = self.to_dict()

tests/quantization/hqq/test_hqq.py

@@ -94,8 +94,7 @@ class HqqConfigTest(unittest.TestCase):
         quantization_config = HqqConfig()
         hqq_orig_config = quantization_config.to_dict()
 
-        for key in hqq_orig_config:
-            self.assertEqual(quantization_config.quant_config[key], hqq_orig_config[key])
+        self.assertEqual(quantization_config.quant_config, hqq_orig_config["quant_config"])
 
 
 @slow
@@ -109,32 +108,7 @@ class HQQTest(unittest.TestCase):
         """
         Simple LLM model testing fp16
         """
-        quant_config = HqqConfig(nbits=8, group_size=64, quant_zero=False, quant_scale=False, axis=0)
-
-        hqq_runner = HQQLLMRunner(
-            model_id=MODEL_ID, quant_config=quant_config, compute_dtype=torch.float16, device=torch_device
-        )
-
-        check_hqqlayer(self, hqq_runner.model.model.layers[0].self_attn.v_proj)
-        check_forward(self, hqq_runner.model)
-
-    def test_f16_quantized_model_with_offloading(self):
-        """
-        Simple LLM model testing bfp16 with meta-data offloading
-        """
-        q4_config = {"nbits": 4, "group_size": 64, "quant_zero": False, "quant_scale": False}
-        q3_config = {"nbits": 3, "group_size": 32, "quant_zero": False, "quant_scale": False, "offload_meta": True}
-        quant_config = HqqConfig(
-            dynamic_config={
-                "self_attn.q_proj": q4_config,
-                "self_attn.k_proj": q4_config,
-                "self_attn.v_proj": q4_config,
-                "self_attn.o_proj": q4_config,
-                "mlp.gate_proj": q3_config,
-                "mlp.up_proj": q3_config,
-                "mlp.down_proj": q3_config,
-            }
-        )
+        quant_config = HqqConfig(nbits=8, group_size=64)
 
         hqq_runner = HQQLLMRunner(
             model_id=MODEL_ID, quant_config=quant_config, compute_dtype=torch.float16, device=torch_device
@@ -157,7 +131,7 @@ class HQQTestMultiGPU(unittest.TestCase):
         Simple LLM model testing fp16 with multi-gpu
         """
 
-        quant_config = HqqConfig(nbits=8, group_size=64, quant_zero=False, quant_scale=False, axis=0)
+        quant_config = HqqConfig(nbits=8, group_size=64)
 
         hqq_runner = HQQLLMRunner(
             model_id=MODEL_ID, quant_config=quant_config, compute_dtype=torch.float16, device="auto"
@@ -165,3 +139,44 @@ class HQQTestMultiGPU(unittest.TestCase):
 
         check_hqqlayer(self, hqq_runner.model.model.layers[0].self_attn.v_proj)
         check_forward(self, hqq_runner.model)
+
+
+@slow
+@require_torch_gpu
+@require_accelerate
+class HQQSerializationTest(unittest.TestCase):
+    def tearDown(self):
+        cleanup()
+
+    def test_model_serialization(self):
+        """
+        Simple HQQ LLM save/load test
+        """
+        quant_config = HqqConfig(nbits=4, group_size=64)
+
+        hqq_runner = HQQLLMRunner(
+            model_id=MODEL_ID, quant_config=quant_config, compute_dtype=torch.float16, device=torch_device
+        )
+
+        input_tensor = torch.zeros((1, 8), dtype=torch.int32, device=torch_device)
+
+        with torch.no_grad():
+            logits_ref = hqq_runner.model.forward(input_tensor).logits
+
+        # Save
+        saved_model_id = "quant_model"
+        hqq_runner.model.save_pretrained(saved_model_id)
+
+        # Remove old model
+        del hqq_runner.model
+        torch.cuda.empty_cache()
+
+        # Load and check if the logits match
+        model_loaded = AutoModelForCausalLM.from_pretrained(
+            "quant_model", torch_dtype=torch.float16, device_map=torch_device, low_cpu_mem_usage=True
+        )
+
+        with torch.no_grad():
+            logits_loaded = model_loaded.forward(input_tensor).logits
+
+        self.assertEqual((logits_loaded - logits_ref).abs().mean().item(), 0)