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vllm.model_executor.layers.vocab_parallel_embedding

DEFAULT_VOCAB_PADDING_SIZE module-attribute

DEFAULT_VOCAB_PADDING_SIZE = 64

ParallelLMHead

Bases: VocabParallelEmbedding

Parallelized LM head.

Output logits weight matrices used in the Sampler. The weight and bias tensors are padded to make sure they are divisible by the number of model parallel GPUs.

Parameters:

Name Type Description Default
num_embeddings int

vocabulary size.

required
embedding_dim int

size of hidden state.

required
bias bool

whether to use bias.

False
params_dtype Optional[dtype]

type of the parameters.

None
org_num_embeddings Optional[int]

original vocabulary size (without LoRA).

None
padding_size int

padding size for the vocabulary.

DEFAULT_VOCAB_PADDING_SIZE
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
class ParallelLMHead(VocabParallelEmbedding):
    """Parallelized LM head.

    Output logits weight matrices used in the Sampler. The weight and bias
    tensors are padded to make sure they are divisible by the number of
    model parallel GPUs.

    Args:
        num_embeddings: vocabulary size.
        embedding_dim: size of hidden state.
        bias: whether to use bias.
        params_dtype: type of the parameters.
        org_num_embeddings: original vocabulary size (without LoRA).
        padding_size: padding size for the vocabulary.
    """

    def __init__(self,
                 num_embeddings: int,
                 embedding_dim: int,
                 bias: bool = False,
                 params_dtype: Optional[torch.dtype] = None,
                 org_num_embeddings: Optional[int] = None,
                 padding_size: int = DEFAULT_VOCAB_PADDING_SIZE,
                 quant_config: Optional[QuantizationConfig] = None,
                 prefix: str = ""):
        super().__init__(num_embeddings, embedding_dim, params_dtype,
                         org_num_embeddings, padding_size, quant_config,
                         prefix)
        self.quant_config = quant_config
        if bias:
            self.bias = Parameter(
                torch.empty(self.num_embeddings_per_partition,
                            dtype=params_dtype))
            set_weight_attrs(self.bias, {
                "output_dim": 0,
                "weight_loader": self.weight_loader,
            })
        else:
            self.register_parameter("bias", None)

    def tie_weights(self, embed_tokens: VocabParallelEmbedding):
        """Tie the weights with word embeddings."""
        # GGUF quantized embed_tokens.
        if self.quant_config and self.quant_config.get_name() == "gguf":
            return embed_tokens
        else:
            self.weight = embed_tokens.weight
            return self

    def forward(self, input_):
        del input_
        raise RuntimeError("LMHead's weights should be used in the sampler.")

bias instance-attribute

bias = Parameter(
    empty(num_embeddings_per_partition, dtype=params_dtype)
)

quant_config instance-attribute

quant_config = quant_config

__init__

__init__(
    num_embeddings: int,
    embedding_dim: int,
    bias: bool = False,
    params_dtype: Optional[dtype] = None,
    org_num_embeddings: Optional[int] = None,
    padding_size: int = DEFAULT_VOCAB_PADDING_SIZE,
    quant_config: Optional[QuantizationConfig] = None,
    prefix: str = "",
)
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def __init__(self,
             num_embeddings: int,
             embedding_dim: int,
             bias: bool = False,
             params_dtype: Optional[torch.dtype] = None,
             org_num_embeddings: Optional[int] = None,
             padding_size: int = DEFAULT_VOCAB_PADDING_SIZE,
             quant_config: Optional[QuantizationConfig] = None,
             prefix: str = ""):
    super().__init__(num_embeddings, embedding_dim, params_dtype,
                     org_num_embeddings, padding_size, quant_config,
                     prefix)
    self.quant_config = quant_config
    if bias:
        self.bias = Parameter(
            torch.empty(self.num_embeddings_per_partition,
                        dtype=params_dtype))
        set_weight_attrs(self.bias, {
            "output_dim": 0,
            "weight_loader": self.weight_loader,
        })
    else:
        self.register_parameter("bias", None)

forward

forward(input_)
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def forward(self, input_):
    del input_
    raise RuntimeError("LMHead's weights should be used in the sampler.")

tie_weights

tie_weights(embed_tokens: VocabParallelEmbedding)

Tie the weights with word embeddings.

Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def tie_weights(self, embed_tokens: VocabParallelEmbedding):
    """Tie the weights with word embeddings."""
    # GGUF quantized embed_tokens.
    if self.quant_config and self.quant_config.get_name() == "gguf":
        return embed_tokens
    else:
        self.weight = embed_tokens.weight
        return self

UnquantizedEmbeddingMethod

Bases: QuantizeMethodBase

Unquantized method for embeddings.

Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
class UnquantizedEmbeddingMethod(QuantizeMethodBase):
    """Unquantized method for embeddings."""

    def create_weights(self, layer: torch.nn.Module,
                       input_size_per_partition: int,
                       output_partition_sizes: list[int], input_size: int,
                       output_size: int, params_dtype: torch.dtype,
                       **extra_weight_attrs):
        """Create weights for embedding layer."""
        weight = Parameter(torch.empty(sum(output_partition_sizes),
                                       input_size_per_partition,
                                       dtype=params_dtype),
                           requires_grad=False)
        set_weight_attrs(weight, {"input_dim": 1, "output_dim": 0})
        layer.register_parameter("weight", weight)
        set_weight_attrs(weight, extra_weight_attrs)

    def apply(self,
              layer: torch.nn.Module,
              x: torch.Tensor,
              bias: Optional[torch.Tensor] = None) -> torch.Tensor:
        return dispatch_unquantized_gemm()(layer, x, layer.weight, bias)

    def embedding(self, layer: torch.nn.Module,
                  input_: torch.Tensor) -> torch.Tensor:
        return F.embedding(input_, layer.weight)

apply

apply(
    layer: Module, x: Tensor, bias: Optional[Tensor] = None
) -> Tensor
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def apply(self,
          layer: torch.nn.Module,
          x: torch.Tensor,
          bias: Optional[torch.Tensor] = None) -> torch.Tensor:
    return dispatch_unquantized_gemm()(layer, x, layer.weight, bias)

create_weights

create_weights(
    layer: Module,
    input_size_per_partition: int,
    output_partition_sizes: list[int],
    input_size: int,
    output_size: int,
    params_dtype: dtype,
    **extra_weight_attrs,
)

Create weights for embedding layer.

Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def create_weights(self, layer: torch.nn.Module,
                   input_size_per_partition: int,
                   output_partition_sizes: list[int], input_size: int,
                   output_size: int, params_dtype: torch.dtype,
                   **extra_weight_attrs):
    """Create weights for embedding layer."""
    weight = Parameter(torch.empty(sum(output_partition_sizes),
                                   input_size_per_partition,
                                   dtype=params_dtype),
                       requires_grad=False)
    set_weight_attrs(weight, {"input_dim": 1, "output_dim": 0})
    layer.register_parameter("weight", weight)
    set_weight_attrs(weight, extra_weight_attrs)

embedding

embedding(layer: Module, input_: Tensor) -> Tensor
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def embedding(self, layer: torch.nn.Module,
              input_: torch.Tensor) -> torch.Tensor:
    return F.embedding(input_, layer.weight)

VocabParallelEmbedding

Bases: Module

Embedding parallelized in the vocabulary dimension.

Adapted from torch.nn.Embedding, note that we pad the vocabulary size to make sure it is divisible by the number of model parallel GPUs.

In order to support various loading methods, we ensure that LoRA-added embeddings are always at the end of TP-sharded tensors. In other words, we shard base embeddings and LoRA embeddings separately (both padded), and place them in the same tensor. In this example, we will have the original vocab size = 1010, added vocab size = 16 and padding to 64. Therefore, the total vocab size with padding will be 1088 (because we first pad 1010 to 1024, add 16, and then pad to 1088). Therefore, the tensor format looks like the following: TP1, rank 0 (no sharding): |< --------BASE-------- >|< -BASE PADDING-- >|< -----LORA------ >|< -LORA PADDING-- >| corresponding token_id: | 0 | 1 | ... | 1009 | -1 | ... | -1 | 1010 | ... | 1025 | -1 | ... | -1 | index: | 0 | 1 | ... | 1009 | 1010 | ... | 1023 | 1024 | ... | 1039 | 1040 | ... | 1087 |

TP2, rank 0: |< --------------------BASE--------------------- >|< -----LORA------ >|< -LORA PADDING- >| corresponding token_id: | 0 | 1 | 2 | ... | 497 | 498 | ... | 511 | 1010 | ... | 1025 | -1 | ... | -1 | index: | 0 | 1 | 2 | ... | 497 | 498 | ... | 511 | 512 | ... | 527 | 528 | ... | 543 | TP2, rank 1: |< -----------BASE----------- >|< -BASE PADDING- >|< -----------LORA PADDING----------- >| corresponding token_id: | 512 | 513 | 514 | ... | 1009 | -1 | ... | -1 | -1 | ... | -1 | -1 | ... | -1 | index: | 0 | 1 | 2 | ... | 497 | 498 | ... | 511 | 512 | ... | 527 | 528 | ... | 543 |

Parameters:

Name Type Description Default
num_embeddings int

vocabulary size.

required
embedding_dim int

size of hidden state.

required
params_dtype Optional[dtype]

type of the parameters.

None
org_num_embeddings Optional[int]

original vocabulary size (without LoRA).

None
padding_size int

padding size for the vocabulary.

DEFAULT_VOCAB_PADDING_SIZE
quant_config Optional[QuantizationConfig]

quant config for the layer

None
prefix str

full name of the layer in the state dict

''
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
class VocabParallelEmbedding(torch.nn.Module):
    """Embedding parallelized in the vocabulary dimension.

    Adapted from torch.nn.Embedding, note that we pad the vocabulary size to
    make sure it is divisible by the number of model parallel GPUs.

    In order to support various loading methods, we ensure that LoRA-added
    embeddings are always at the end of TP-sharded tensors. In other words,
    we shard base embeddings and LoRA embeddings separately (both padded),
    and place them in the same tensor.
    In this example, we will have the original vocab size = 1010,
    added vocab size = 16 and padding to 64. Therefore, the total
    vocab size with padding will be 1088 (because we first pad 1010 to
    1024, add 16, and then pad to 1088).
    Therefore, the tensor format looks like the following:
    TP1, rank 0 (no sharding):
                            |< --------BASE-------- >|< -BASE PADDING-- >|< -----LORA------ >|< -LORA PADDING-- >|
    corresponding token_id: |  0  |  1  | ... | 1009 |  -1  | ... |  -1  | 1010 | ... | 1025 |  -1  | ... |  -1  |
                     index: |  0  |  1  | ... | 1009 | 1010 | ... | 1023 | 1024 | ... | 1039 | 1040 | ... | 1087 |

    TP2, rank 0:
                            |< --------------------BASE--------------------- >|< -----LORA------ >|< -LORA PADDING- >|
    corresponding token_id: |  0  |  1  |  2  | ... | 497  | 498 | ...  | 511 | 1010 | ... | 1025 |  -1  | ... |  -1 |
                     index: |  0  |  1  |  2  | ... | 497  | 498 | ...  | 511 | 512  | ... | 527  |  528 | ... | 543 |
    TP2, rank 1:
                            |< -----------BASE----------- >|< -BASE PADDING- >|< -----------LORA PADDING----------- >|
    corresponding token_id: | 512 | 513 | 514 | ... | 1009 | -1  | ...  | -1  |  -1  | ... |  -1  | -1  | ... |   -1 |
                     index: |  0  |  1  |  2  | ... | 497  | 498 | ...  | 511 | 512  | ... | 527  | 528 | ... |  543 |

    Args:
        num_embeddings: vocabulary size.
        embedding_dim: size of hidden state.
        params_dtype: type of the parameters.
        org_num_embeddings: original vocabulary size (without LoRA).
        padding_size: padding size for the vocabulary.
        quant_config: quant config for the layer
        prefix: full name of the layer in the state dict
    """  # noqa: E501

    def __init__(self,
                 num_embeddings: int,
                 embedding_dim: int,
                 params_dtype: Optional[torch.dtype] = None,
                 org_num_embeddings: Optional[int] = None,
                 padding_size: int = DEFAULT_VOCAB_PADDING_SIZE,
                 quant_config: Optional[QuantizationConfig] = None,
                 prefix: str = ""):
        super().__init__()

        # Keep the input dimensions.
        tp_rank = get_tensor_model_parallel_rank()
        self.tp_size = get_tensor_model_parallel_world_size()
        self.num_embeddings = num_embeddings
        self.padding_size = padding_size
        self.org_vocab_size = org_num_embeddings or num_embeddings
        num_added_embeddings = num_embeddings - self.org_vocab_size
        self.org_vocab_size_padded = pad_vocab_size(self.org_vocab_size,
                                                    self.padding_size)
        self.num_embeddings_padded = pad_vocab_size(
            self.org_vocab_size_padded + num_added_embeddings,
            self.padding_size)
        assert self.org_vocab_size_padded <= self.num_embeddings_padded

        self.shard_indices = self._get_indices(self.num_embeddings_padded,
                                               self.org_vocab_size_padded,
                                               self.num_embeddings,
                                               self.org_vocab_size, tp_rank,
                                               self.tp_size)
        self.embedding_dim = embedding_dim

        quant_method = None
        if quant_config is not None:
            quant_method = quant_config.get_quant_method(self, prefix=prefix)
        if quant_method is None:
            quant_method = UnquantizedEmbeddingMethod()

        # If we are making an embedding layer, then our quantization linear
        # method must implement the embedding operation. If we are another
        # layer type like ParallelLMHead, this is not important.
        is_embedding_layer = type(self) is VocabParallelEmbedding
        quant_method_implements_embedding = method_has_implemented_embedding(
            type(quant_method))
        if is_embedding_layer and not quant_method_implements_embedding:
            raise NotImplementedError(
                f"The class {type(quant_method).__name__} must implement "
                "the 'embedding' method, see UnquantizedEmbeddingMethod.")

        self.quant_method: QuantizeMethodBase = quant_method

        if params_dtype is None:
            params_dtype = torch.get_default_dtype()
        # Divide the weight matrix along the vocaburaly dimension.
        self.num_added_embeddings = self.num_embeddings - self.org_vocab_size
        self.num_embeddings_per_partition = divide(self.num_embeddings_padded,
                                                   self.tp_size)
        assert (self.shard_indices.num_elements_padded ==
                self.num_embeddings_per_partition)
        self.num_org_embeddings_per_partition = (
            self.shard_indices.org_vocab_end_index -
            self.shard_indices.org_vocab_start_index)
        self.num_added_embeddings_per_partition = (
            self.shard_indices.added_vocab_end_index -
            self.shard_indices.added_vocab_start_index)

        self.quant_method.create_weights(self,
                                         self.embedding_dim,
                                         [self.num_embeddings_per_partition],
                                         self.embedding_dim,
                                         self.num_embeddings_padded,
                                         params_dtype=params_dtype,
                                         weight_loader=self.weight_loader)

    @classmethod
    def _get_indices(cls, vocab_size_padded: int, org_vocab_size_padded: int,
                     vocab_size: int, org_vocab_size: int, tp_rank: int,
                     tp_size: int) -> VocabParallelEmbeddingShardIndices:
        """Get start and end indices for vocab parallel embedding, following the
        layout outlined in the class docstring, based on the given tp_rank and
        tp_size."""
        num_added_embeddings_padded = vocab_size_padded - org_vocab_size_padded
        padded_org_vocab_start_index, padded_org_vocab_end_index = (
            vocab_range_from_global_vocab_size(org_vocab_size_padded, tp_rank,
                                               tp_size))
        padded_added_vocab_start_index, padded_added_vocab_end_index = (
            vocab_range_from_global_vocab_size(num_added_embeddings_padded,
                                               tp_rank,
                                               tp_size,
                                               offset=org_vocab_size))
        # remove padding
        org_vocab_start_index = min(padded_org_vocab_start_index,
                                    org_vocab_size)
        org_vocab_end_index = min(padded_org_vocab_end_index, org_vocab_size)
        added_vocab_start_index = min(padded_added_vocab_start_index,
                                      vocab_size)
        added_vocab_end_index = min(padded_added_vocab_end_index, vocab_size)
        return VocabParallelEmbeddingShardIndices(
            padded_org_vocab_start_index, padded_org_vocab_end_index,
            padded_added_vocab_start_index, padded_added_vocab_end_index,
            org_vocab_start_index, org_vocab_end_index,
            added_vocab_start_index, added_vocab_end_index)

    def get_sharded_to_full_mapping(self) -> Optional[list[int]]:
        """Get a mapping that can be used to reindex the gathered
        logits for sampling.

        During sampling, we gather logits from all ranks. The relationship
        of index->token_id will follow the same format as outlined in the class
        docstring. However, after the gather, we want to reindex the final
        logits tensor to map index->token_id one-to-one (the index is always
        equal the token_id it corresponds to). The indices returned by this
        method allow us to do that.
        """
        if self.tp_size < 2:
            return None

        base_embeddings: list[int] = []
        added_embeddings: list[int] = []
        padding: list[int] = []
        for tp_rank in range(self.tp_size):
            shard_indices = self._get_indices(self.num_embeddings_padded,
                                              self.org_vocab_size_padded,
                                              self.num_embeddings,
                                              self.org_vocab_size, tp_rank,
                                              self.tp_size)
            range_start = self.num_embeddings_per_partition * tp_rank
            range_end = self.num_embeddings_per_partition * (tp_rank + 1)
            base_embeddings.extend(
                range(range_start,
                      range_start + shard_indices.num_org_elements))
            padding.extend(
                range(range_start + shard_indices.num_org_elements,
                      range_start + shard_indices.num_org_elements_padded))
            added_embeddings.extend(
                range(
                    range_start + shard_indices.num_org_elements_padded,
                    range_start + shard_indices.num_org_elements_padded +
                    shard_indices.num_added_elements))
            padding.extend(
                range(
                    range_start + shard_indices.num_org_elements_padded +
                    shard_indices.num_added_elements,
                    range_start + shard_indices.num_org_elements_padded +
                    shard_indices.num_added_elements_padded))
            assert (range_start + shard_indices.num_org_elements_padded +
                    shard_indices.num_added_elements_padded == range_end)
        ret = base_embeddings + added_embeddings + padding
        assert len(ret) == self.num_embeddings_padded
        return ret

    def weight_loader(self, param: Parameter, loaded_weight: torch.Tensor):
        output_dim = getattr(param, "output_dim", None)
        packed_dim = getattr(param, "packed_dim", None)

        # If the parameter is a gguf weight, then load it directly.
        if getattr(param, "is_gguf_weight_type", None):
            param.data.copy_(loaded_weight)
            param.weight_type = loaded_weight.item()
            return
        elif isinstance(param, UninitializedParameter):
            shape = list(loaded_weight.shape)
            if output_dim is not None:
                shape[output_dim] = self.num_embeddings_per_partition
            param.materialize(tuple(shape), dtype=loaded_weight.dtype)

        # If parameter does not have output dim, then it should
        # be copied onto all gpus (e.g. g_idx for act_order gptq).
        if output_dim is None:
            assert param.data.shape == loaded_weight.shape
            param.data.copy_(loaded_weight)
            return

        # Shard indexes for loading the weight
        start_idx = self.shard_indices.org_vocab_start_index
        shard_size = self.shard_indices.org_vocab_end_index - start_idx

        # If param packed on the same dim we are sharding on, then
        # need to adjust offsets of loaded weight by pack_factor.
        if packed_dim is not None and packed_dim == output_dim:
            packed_factor = param.packed_factor if isinstance(
                param, BasevLLMParameter) else param.pack_factor
            assert loaded_weight.shape[output_dim] == (self.org_vocab_size //
                                                       param.packed_factor)
            start_idx = start_idx // packed_factor
            shard_size = shard_size // packed_factor
        else:
            assert loaded_weight.shape[output_dim] == self.org_vocab_size

        # Copy the data. Select chunk corresponding to current shard.
        loaded_weight = loaded_weight.narrow(output_dim, start_idx, shard_size)

        if current_platform.is_hpu():
            # FIXME(kzawora): Weight copy with slicing bugs out on Gaudi here,
            # so we're using a workaround. Remove this when fixed in
            # HPU PT bridge.
            padded_weight = torch.cat([
                loaded_weight,
                torch.zeros(param.shape[0] - loaded_weight.shape[0],
                            *loaded_weight.shape[1:])
            ])
            param.data.copy_(padded_weight)
        else:
            param[:loaded_weight.shape[0]].data.copy_(loaded_weight)
            param[loaded_weight.shape[0]:].data.fill_(0)

    def forward(self, input_):
        if self.tp_size > 1:
            # Build the mask.
            masked_input, input_mask = get_masked_input_and_mask(
                input_, self.shard_indices.org_vocab_start_index,
                self.shard_indices.org_vocab_end_index,
                self.shard_indices.num_org_vocab_padding,
                self.shard_indices.added_vocab_start_index,
                self.shard_indices.added_vocab_end_index)
        else:
            masked_input = input_
        # Get the embeddings.
        output_parallel = self.quant_method.embedding(self,
                                                      masked_input.long())
        # Mask the output embedding.
        if self.tp_size > 1:
            output_parallel.masked_fill_(input_mask.unsqueeze(-1), 0)
        # Reduce across all the model parallel GPUs.
        output = tensor_model_parallel_all_reduce(output_parallel)
        return output

    def extra_repr(self) -> str:
        s = f"num_embeddings={self.num_embeddings_per_partition}"
        s += f", embedding_dim={self.embedding_dim}"
        s += f", org_vocab_size={self.org_vocab_size}"
        s += f', num_embeddings_padded={self.num_embeddings_padded}'
        s += f', tp_size={self.tp_size}'
        return s

embedding_dim instance-attribute

embedding_dim = embedding_dim

num_added_embeddings instance-attribute

num_added_embeddings = num_embeddings - org_vocab_size

num_added_embeddings_per_partition instance-attribute

num_added_embeddings_per_partition = (
    added_vocab_end_index - added_vocab_start_index
)

num_embeddings instance-attribute

num_embeddings = num_embeddings

num_embeddings_padded instance-attribute

num_embeddings_padded = pad_vocab_size(
    org_vocab_size_padded + num_added_embeddings,
    padding_size,
)

num_embeddings_per_partition instance-attribute

num_embeddings_per_partition = divide(
    num_embeddings_padded, tp_size
)

num_org_embeddings_per_partition instance-attribute

num_org_embeddings_per_partition = (
    org_vocab_end_index - org_vocab_start_index
)

org_vocab_size instance-attribute

org_vocab_size = org_num_embeddings or num_embeddings

org_vocab_size_padded instance-attribute

org_vocab_size_padded = pad_vocab_size(
    org_vocab_size, padding_size
)

padding_size instance-attribute

padding_size = padding_size

quant_method instance-attribute

quant_method: QuantizeMethodBase = quant_method

shard_indices instance-attribute

shard_indices = _get_indices(
    num_embeddings_padded,
    org_vocab_size_padded,
    num_embeddings,
    org_vocab_size,
    tp_rank,
    tp_size,
)

tp_size instance-attribute

__init__

__init__(
    num_embeddings: int,
    embedding_dim: int,
    params_dtype: Optional[dtype] = None,
    org_num_embeddings: Optional[int] = None,
    padding_size: int = DEFAULT_VOCAB_PADDING_SIZE,
    quant_config: Optional[QuantizationConfig] = None,
    prefix: str = "",
)
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def __init__(self,
             num_embeddings: int,
             embedding_dim: int,
             params_dtype: Optional[torch.dtype] = None,
             org_num_embeddings: Optional[int] = None,
             padding_size: int = DEFAULT_VOCAB_PADDING_SIZE,
             quant_config: Optional[QuantizationConfig] = None,
             prefix: str = ""):
    super().__init__()

    # Keep the input dimensions.
    tp_rank = get_tensor_model_parallel_rank()
    self.tp_size = get_tensor_model_parallel_world_size()
    self.num_embeddings = num_embeddings
    self.padding_size = padding_size
    self.org_vocab_size = org_num_embeddings or num_embeddings
    num_added_embeddings = num_embeddings - self.org_vocab_size
    self.org_vocab_size_padded = pad_vocab_size(self.org_vocab_size,
                                                self.padding_size)
    self.num_embeddings_padded = pad_vocab_size(
        self.org_vocab_size_padded + num_added_embeddings,
        self.padding_size)
    assert self.org_vocab_size_padded <= self.num_embeddings_padded

    self.shard_indices = self._get_indices(self.num_embeddings_padded,
                                           self.org_vocab_size_padded,
                                           self.num_embeddings,
                                           self.org_vocab_size, tp_rank,
                                           self.tp_size)
    self.embedding_dim = embedding_dim

    quant_method = None
    if quant_config is not None:
        quant_method = quant_config.get_quant_method(self, prefix=prefix)
    if quant_method is None:
        quant_method = UnquantizedEmbeddingMethod()

    # If we are making an embedding layer, then our quantization linear
    # method must implement the embedding operation. If we are another
    # layer type like ParallelLMHead, this is not important.
    is_embedding_layer = type(self) is VocabParallelEmbedding
    quant_method_implements_embedding = method_has_implemented_embedding(
        type(quant_method))
    if is_embedding_layer and not quant_method_implements_embedding:
        raise NotImplementedError(
            f"The class {type(quant_method).__name__} must implement "
            "the 'embedding' method, see UnquantizedEmbeddingMethod.")

    self.quant_method: QuantizeMethodBase = quant_method

    if params_dtype is None:
        params_dtype = torch.get_default_dtype()
    # Divide the weight matrix along the vocaburaly dimension.
    self.num_added_embeddings = self.num_embeddings - self.org_vocab_size
    self.num_embeddings_per_partition = divide(self.num_embeddings_padded,
                                               self.tp_size)
    assert (self.shard_indices.num_elements_padded ==
            self.num_embeddings_per_partition)
    self.num_org_embeddings_per_partition = (
        self.shard_indices.org_vocab_end_index -
        self.shard_indices.org_vocab_start_index)
    self.num_added_embeddings_per_partition = (
        self.shard_indices.added_vocab_end_index -
        self.shard_indices.added_vocab_start_index)

    self.quant_method.create_weights(self,
                                     self.embedding_dim,
                                     [self.num_embeddings_per_partition],
                                     self.embedding_dim,
                                     self.num_embeddings_padded,
                                     params_dtype=params_dtype,
                                     weight_loader=self.weight_loader)

_get_indices classmethod

_get_indices(
    vocab_size_padded: int,
    org_vocab_size_padded: int,
    vocab_size: int,
    org_vocab_size: int,
    tp_rank: int,
    tp_size: int,
) -> VocabParallelEmbeddingShardIndices

Get start and end indices for vocab parallel embedding, following the layout outlined in the class docstring, based on the given tp_rank and tp_size.

Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
@classmethod
def _get_indices(cls, vocab_size_padded: int, org_vocab_size_padded: int,
                 vocab_size: int, org_vocab_size: int, tp_rank: int,
                 tp_size: int) -> VocabParallelEmbeddingShardIndices:
    """Get start and end indices for vocab parallel embedding, following the
    layout outlined in the class docstring, based on the given tp_rank and
    tp_size."""
    num_added_embeddings_padded = vocab_size_padded - org_vocab_size_padded
    padded_org_vocab_start_index, padded_org_vocab_end_index = (
        vocab_range_from_global_vocab_size(org_vocab_size_padded, tp_rank,
                                           tp_size))
    padded_added_vocab_start_index, padded_added_vocab_end_index = (
        vocab_range_from_global_vocab_size(num_added_embeddings_padded,
                                           tp_rank,
                                           tp_size,
                                           offset=org_vocab_size))
    # remove padding
    org_vocab_start_index = min(padded_org_vocab_start_index,
                                org_vocab_size)
    org_vocab_end_index = min(padded_org_vocab_end_index, org_vocab_size)
    added_vocab_start_index = min(padded_added_vocab_start_index,
                                  vocab_size)
    added_vocab_end_index = min(padded_added_vocab_end_index, vocab_size)
    return VocabParallelEmbeddingShardIndices(
        padded_org_vocab_start_index, padded_org_vocab_end_index,
        padded_added_vocab_start_index, padded_added_vocab_end_index,
        org_vocab_start_index, org_vocab_end_index,
        added_vocab_start_index, added_vocab_end_index)

extra_repr

extra_repr() -> str
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def extra_repr(self) -> str:
    s = f"num_embeddings={self.num_embeddings_per_partition}"
    s += f", embedding_dim={self.embedding_dim}"
    s += f", org_vocab_size={self.org_vocab_size}"
    s += f', num_embeddings_padded={self.num_embeddings_padded}'
    s += f', tp_size={self.tp_size}'
    return s

forward

forward(input_)
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def forward(self, input_):
    if self.tp_size > 1:
        # Build the mask.
        masked_input, input_mask = get_masked_input_and_mask(
            input_, self.shard_indices.org_vocab_start_index,
            self.shard_indices.org_vocab_end_index,
            self.shard_indices.num_org_vocab_padding,
            self.shard_indices.added_vocab_start_index,
            self.shard_indices.added_vocab_end_index)
    else:
        masked_input = input_
    # Get the embeddings.
    output_parallel = self.quant_method.embedding(self,
                                                  masked_input.long())
    # Mask the output embedding.
    if self.tp_size > 1:
        output_parallel.masked_fill_(input_mask.unsqueeze(-1), 0)
    # Reduce across all the model parallel GPUs.
    output = tensor_model_parallel_all_reduce(output_parallel)
    return output

get_sharded_to_full_mapping

get_sharded_to_full_mapping() -> Optional[list[int]]

Get a mapping that can be used to reindex the gathered logits for sampling.

During sampling, we gather logits from all ranks. The relationship of index->token_id will follow the same format as outlined in the class docstring. However, after the gather, we want to reindex the final logits tensor to map index->token_id one-to-one (the index is always equal the token_id it corresponds to). The indices returned by this method allow us to do that.

Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def get_sharded_to_full_mapping(self) -> Optional[list[int]]:
    """Get a mapping that can be used to reindex the gathered
    logits for sampling.

    During sampling, we gather logits from all ranks. The relationship
    of index->token_id will follow the same format as outlined in the class
    docstring. However, after the gather, we want to reindex the final
    logits tensor to map index->token_id one-to-one (the index is always
    equal the token_id it corresponds to). The indices returned by this
    method allow us to do that.
    """
    if self.tp_size < 2:
        return None

    base_embeddings: list[int] = []
    added_embeddings: list[int] = []
    padding: list[int] = []
    for tp_rank in range(self.tp_size):
        shard_indices = self._get_indices(self.num_embeddings_padded,
                                          self.org_vocab_size_padded,
                                          self.num_embeddings,
                                          self.org_vocab_size, tp_rank,
                                          self.tp_size)
        range_start = self.num_embeddings_per_partition * tp_rank
        range_end = self.num_embeddings_per_partition * (tp_rank + 1)
        base_embeddings.extend(
            range(range_start,
                  range_start + shard_indices.num_org_elements))
        padding.extend(
            range(range_start + shard_indices.num_org_elements,
                  range_start + shard_indices.num_org_elements_padded))
        added_embeddings.extend(
            range(
                range_start + shard_indices.num_org_elements_padded,
                range_start + shard_indices.num_org_elements_padded +
                shard_indices.num_added_elements))
        padding.extend(
            range(
                range_start + shard_indices.num_org_elements_padded +
                shard_indices.num_added_elements,
                range_start + shard_indices.num_org_elements_padded +
                shard_indices.num_added_elements_padded))
        assert (range_start + shard_indices.num_org_elements_padded +
                shard_indices.num_added_elements_padded == range_end)
    ret = base_embeddings + added_embeddings + padding
    assert len(ret) == self.num_embeddings_padded
    return ret

weight_loader

weight_loader(param: Parameter, loaded_weight: Tensor)
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def weight_loader(self, param: Parameter, loaded_weight: torch.Tensor):
    output_dim = getattr(param, "output_dim", None)
    packed_dim = getattr(param, "packed_dim", None)

    # If the parameter is a gguf weight, then load it directly.
    if getattr(param, "is_gguf_weight_type", None):
        param.data.copy_(loaded_weight)
        param.weight_type = loaded_weight.item()
        return
    elif isinstance(param, UninitializedParameter):
        shape = list(loaded_weight.shape)
        if output_dim is not None:
            shape[output_dim] = self.num_embeddings_per_partition
        param.materialize(tuple(shape), dtype=loaded_weight.dtype)

    # If parameter does not have output dim, then it should
    # be copied onto all gpus (e.g. g_idx for act_order gptq).
    if output_dim is None:
        assert param.data.shape == loaded_weight.shape
        param.data.copy_(loaded_weight)
        return

    # Shard indexes for loading the weight
    start_idx = self.shard_indices.org_vocab_start_index
    shard_size = self.shard_indices.org_vocab_end_index - start_idx

    # If param packed on the same dim we are sharding on, then
    # need to adjust offsets of loaded weight by pack_factor.
    if packed_dim is not None and packed_dim == output_dim:
        packed_factor = param.packed_factor if isinstance(
            param, BasevLLMParameter) else param.pack_factor
        assert loaded_weight.shape[output_dim] == (self.org_vocab_size //
                                                   param.packed_factor)
        start_idx = start_idx // packed_factor
        shard_size = shard_size // packed_factor
    else:
        assert loaded_weight.shape[output_dim] == self.org_vocab_size

    # Copy the data. Select chunk corresponding to current shard.
    loaded_weight = loaded_weight.narrow(output_dim, start_idx, shard_size)

    if current_platform.is_hpu():
        # FIXME(kzawora): Weight copy with slicing bugs out on Gaudi here,
        # so we're using a workaround. Remove this when fixed in
        # HPU PT bridge.
        padded_weight = torch.cat([
            loaded_weight,
            torch.zeros(param.shape[0] - loaded_weight.shape[0],
                        *loaded_weight.shape[1:])
        ])
        param.data.copy_(padded_weight)
    else:
        param[:loaded_weight.shape[0]].data.copy_(loaded_weight)
        param[loaded_weight.shape[0]:].data.fill_(0)

VocabParallelEmbeddingShardIndices dataclass

Indices for a shard of a vocab parallel embedding.

Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
@dataclass
class VocabParallelEmbeddingShardIndices:
    """Indices for a shard of a vocab parallel embedding."""
    padded_org_vocab_start_index: int
    padded_org_vocab_end_index: int
    padded_added_vocab_start_index: int
    padded_added_vocab_end_index: int

    org_vocab_start_index: int
    org_vocab_end_index: int
    added_vocab_start_index: int
    added_vocab_end_index: int

    @property
    def num_org_elements(self) -> int:
        return self.org_vocab_end_index - self.org_vocab_start_index

    @property
    def num_added_elements(self) -> int:
        return self.added_vocab_end_index - self.added_vocab_start_index

    @property
    def num_org_elements_padded(self) -> int:
        return (self.padded_org_vocab_end_index -
                self.padded_org_vocab_start_index)

    @property
    def num_added_elements_padded(self) -> int:
        return (self.padded_added_vocab_end_index -
                self.padded_added_vocab_start_index)

    @property
    def num_org_vocab_padding(self) -> int:
        return self.num_org_elements_padded - self.num_org_elements

    @property
    def num_added_vocab_padding(self) -> int:
        return self.num_added_elements_padded - self.num_added_elements

    @property
    def num_elements_padded(self) -> int:
        return self.num_org_elements_padded + self.num_added_elements_padded

    def __post_init__(self):
        # sanity checks
        assert (self.padded_org_vocab_start_index
                <= self.padded_org_vocab_end_index)
        assert (self.padded_added_vocab_start_index
                <= self.padded_added_vocab_end_index)

        assert self.org_vocab_start_index <= self.org_vocab_end_index
        assert self.added_vocab_start_index <= self.added_vocab_end_index

        assert self.org_vocab_start_index <= self.padded_org_vocab_start_index
        assert (self.added_vocab_start_index
                <= self.padded_added_vocab_start_index)
        assert self.org_vocab_end_index <= self.padded_org_vocab_end_index
        assert self.added_vocab_end_index <= self.padded_added_vocab_end_index

        assert self.num_org_elements <= self.num_org_elements_padded
        assert self.num_added_elements <= self.num_added_elements_padded

added_vocab_end_index instance-attribute

added_vocab_end_index: int

added_vocab_start_index instance-attribute

added_vocab_start_index: int

num_added_elements property

num_added_elements: int

num_added_elements_padded property

num_added_elements_padded: int

num_added_vocab_padding property

num_added_vocab_padding: int

num_elements_padded property

num_elements_padded: int

num_org_elements property

num_org_elements: int

num_org_elements_padded property

num_org_elements_padded: int

num_org_vocab_padding property

num_org_vocab_padding: int

org_vocab_end_index instance-attribute

org_vocab_end_index: int

org_vocab_start_index instance-attribute

org_vocab_start_index: int

padded_added_vocab_end_index instance-attribute

padded_added_vocab_end_index: int

padded_added_vocab_start_index instance-attribute

padded_added_vocab_start_index: int

padded_org_vocab_end_index instance-attribute

padded_org_vocab_end_index: int

padded_org_vocab_start_index instance-attribute

padded_org_vocab_start_index: int

__init__

__init__(
    padded_org_vocab_start_index: int,
    padded_org_vocab_end_index: int,
    padded_added_vocab_start_index: int,
    padded_added_vocab_end_index: int,
    org_vocab_start_index: int,
    org_vocab_end_index: int,
    added_vocab_start_index: int,
    added_vocab_end_index: int,
) -> None

__post_init__

__post_init__()
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def __post_init__(self):
    # sanity checks
    assert (self.padded_org_vocab_start_index
            <= self.padded_org_vocab_end_index)
    assert (self.padded_added_vocab_start_index
            <= self.padded_added_vocab_end_index)

    assert self.org_vocab_start_index <= self.org_vocab_end_index
    assert self.added_vocab_start_index <= self.added_vocab_end_index

    assert self.org_vocab_start_index <= self.padded_org_vocab_start_index
    assert (self.added_vocab_start_index
            <= self.padded_added_vocab_start_index)
    assert self.org_vocab_end_index <= self.padded_org_vocab_end_index
    assert self.added_vocab_end_index <= self.padded_added_vocab_end_index

    assert self.num_org_elements <= self.num_org_elements_padded
    assert self.num_added_elements <= self.num_added_elements_padded

get_masked_input_and_mask

get_masked_input_and_mask(
    input_: Tensor,
    org_vocab_start_index: int,
    org_vocab_end_index: int,
    num_org_vocab_padding: int,
    added_vocab_start_index: int,
    added_vocab_end_index: int,
) -> tuple[Tensor, Tensor]
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
@torch.compile(dynamic=True, backend=current_platform.simple_compile_backend)
def get_masked_input_and_mask(
        input_: torch.Tensor, org_vocab_start_index: int,
        org_vocab_end_index: int, num_org_vocab_padding: int,
        added_vocab_start_index: int,
        added_vocab_end_index: int) -> tuple[torch.Tensor, torch.Tensor]:
    # torch.compile will fuse all of the pointwise ops below
    # into a single kernel, making it very fast
    org_vocab_mask = (input_ >= org_vocab_start_index) & (
        input_ < org_vocab_end_index)
    added_vocab_mask = (input_ >= added_vocab_start_index) & (
        input_ < added_vocab_end_index)
    added_offset = added_vocab_start_index - (
        org_vocab_end_index - org_vocab_start_index) - num_org_vocab_padding
    valid_offset = (org_vocab_start_index *
                    org_vocab_mask) + (added_offset * added_vocab_mask)
    vocab_mask = org_vocab_mask | added_vocab_mask
    input_ = vocab_mask * (input_ - valid_offset)
    return input_, ~vocab_mask

pad_vocab_size

pad_vocab_size(
    vocab_size: int,
    pad_to: int = DEFAULT_VOCAB_PADDING_SIZE,
) -> int

Pad the vocab size to the given value.

Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def pad_vocab_size(vocab_size: int,
                   pad_to: int = DEFAULT_VOCAB_PADDING_SIZE) -> int:
    """Pad the vocab size to the given value."""
    return ((vocab_size + pad_to - 1) // pad_to) * pad_to

vocab_range_from_global_vocab_size

vocab_range_from_global_vocab_size(
    global_vocab_size: int,
    rank: int,
    world_size: int,
    offset: int = 0,
) -> Sequence[int]
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def vocab_range_from_global_vocab_size(global_vocab_size: int,
                                       rank: int,
                                       world_size: int,
                                       offset: int = 0) -> Sequence[int]:
    per_partition_vocab_size = divide(global_vocab_size, world_size)
    return vocab_range_from_per_partition_vocab_size(per_partition_vocab_size,
                                                     rank,
                                                     offset=offset)

vocab_range_from_per_partition_vocab_size

vocab_range_from_per_partition_vocab_size(
    per_partition_vocab_size: int,
    rank: int,
    offset: int = 0,
) -> Sequence[int]
Source code in vllm/model_executor/layers/vocab_parallel_embedding.py
def vocab_range_from_per_partition_vocab_size(
        per_partition_vocab_size: int,
        rank: int,
        offset: int = 0) -> Sequence[int]:
    index_f = rank * per_partition_vocab_size
    index_l = index_f + per_partition_vocab_size
    return index_f + offset, index_l + offset