vllm/vllm/v1/worker/tpu_model_runner.py
Alexander Matveev 9a2160fa55
[V1] TPU CI - Add basic perf regression test (#15414)
Signed-off-by: Alexander Matveev <amatveev@redhat.com>
2025-03-31 13:25:20 -04:00

1032 lines
46 KiB
Python

# SPDX-License-Identifier: Apache-2.0
import bisect
import time
from typing import TYPE_CHECKING, Optional, cast
from unittest.mock import patch
import numpy as np
import torch
import torch.distributed
import torch.nn as nn
# TPU XLA related
import torch_xla.core.xla_model as xm
import torch_xla.runtime as xr
import vllm.envs as envs
from vllm.attention.backends.abstract import AttentionType
from vllm.attention.layer import Attention
from vllm.config import VllmConfig
from vllm.forward_context import set_forward_context
from vllm.logger import init_logger
from vllm.model_executor.model_loader import get_model
from vllm.multimodal import MULTIMODAL_REGISTRY, MultiModalKwargs
from vllm.multimodal.utils import group_mm_inputs_by_modality
from vllm.sampling_params import SamplingType
from vllm.sequence import IntermediateTensors
from vllm.utils import LayerBlockType, cdiv, is_pin_memory_available
from vllm.v1.attention.backends.pallas import (NUM_KV_PAGES_PER_BLOCK,
PallasAttentionBackend,
PallasMetadata)
from vllm.v1.core.encoder_cache_manager import compute_encoder_budget
from vllm.v1.kv_cache_interface import (FullAttentionSpec, KVCacheConfig,
KVCacheSpec)
from vllm.v1.outputs import (EMPTY_MODEL_RUNNER_OUTPUT, LogprobsTensors,
ModelRunnerOutput, SamplerOutput)
from vllm.v1.sample.tpu.metadata import TPUSupportedSamplingMetadata
from vllm.v1.sample.tpu.sampler import Sampler as TPUSampler
from vllm.v1.utils import bind_kv_cache
from vllm.v1.worker.gpu_input_batch import CachedRequestState, InputBatch
from .utils import sanity_check_mm_encoder_outputs
if TYPE_CHECKING:
from vllm.v1.core.sched.output import SchedulerOutput
logger = init_logger(__name__)
# Here we utilize the behavior that out-of-bound index is ignored.
# FIXME(woosuk): Find a more reliable way to prevent possible bugs.
_PAD_SLOT_ID = 1_000_000_000
INVALID_TOKEN_ID = -1
# Smallest output size
MIN_NUM_SEQS = 8
class TPUModelRunner:
def __init__(
self,
vllm_config: VllmConfig,
device: torch.device,
):
self.vllm_config = vllm_config
self.model_config = vllm_config.model_config
self.cache_config = vllm_config.cache_config
self.lora_config = vllm_config.lora_config
self.load_config = vllm_config.load_config
self.parallel_config = vllm_config.parallel_config
self.scheduler_config = vllm_config.scheduler_config
self.speculative_config = vllm_config.speculative_config
self.prompt_adapter_config = vllm_config.prompt_adapter_config
self.observability_config = vllm_config.observability_config
self.device_config = vllm_config.device_config
model_config = self.model_config
cache_config = self.cache_config
scheduler_config = self.scheduler_config
parallel_config = self.parallel_config
self.device = device
self.check_recompilation = envs.VLLM_XLA_CHECK_RECOMPILATION
self.enforce_eager = model_config.enforce_eager
self.num_xla_graphs = 0
self._update_num_xla_graphs("init")
self.pin_memory = is_pin_memory_available()
self.dtype = self.model_config.dtype
self._hidden_states_dtype = self.dtype
self.is_multimodal_model = model_config.is_multimodal_model
self.sliding_window = model_config.get_sliding_window()
self.block_size = cache_config.block_size
self.max_model_len = model_config.max_model_len
self.max_num_blocks_per_req = cdiv(self.max_model_len, self.block_size)
self.max_num_tokens = scheduler_config.max_num_batched_tokens
# InputBatch needs to work with sampling tensors greater than padding
# to avoid dynamic shapes. Also, avoid suboptimal alignment.
self.max_num_reqs = max(scheduler_config.max_num_seqs, MIN_NUM_SEQS)
# Model-related.
self.num_attn_layers = model_config.get_num_layers_by_block_type(
parallel_config, LayerBlockType.attention)
self.num_query_heads = model_config.get_num_attention_heads(
parallel_config)
self.num_kv_heads = model_config.get_num_kv_heads(parallel_config)
self.head_size = model_config.get_head_size()
self.hidden_size = model_config.get_hidden_size()
# Multi-modal data support
self.mm_registry = MULTIMODAL_REGISTRY
self.uses_mrope = model_config.uses_mrope
# TODO: Support M-RoPE (e.g, Qwen2-VL)
assert not self.uses_mrope, "TPU does not support M-RoPE yet."
encoder_compute_budget, encoder_cache_size = compute_encoder_budget(
model_config=model_config,
scheduler_config=scheduler_config,
mm_registry=self.mm_registry,
)
self.max_num_encoder_input_tokens = encoder_compute_budget
self.encoder_cache_size = encoder_cache_size
# Lazy initialization
# self.model: nn.Module # Set after load_model
self.kv_caches: list[torch.Tensor] = []
# req_id -> (input_id -> encoder_output)
self.encoder_cache: dict[str, dict[int, torch.Tensor]] = {}
# Request states.
self.requests: dict[str, CachedRequestState] = {}
# Persistent batch.
self.input_batch = InputBatch(
max_num_reqs=self.max_num_reqs,
max_model_len=self.max_model_len,
max_num_blocks_per_req=self.max_num_blocks_per_req,
device=self.device,
pin_memory=self.pin_memory,
vocab_size=model_config.get_vocab_size(),
)
# Cached torch/numpy tensor
# The pytorch tensor and numpy array share the same buffer.
# Sometimes the numpy op is faster so we create both.
self.input_ids_cpu = torch.zeros(self.max_num_tokens,
dtype=torch.int32,
device="cpu")
self.input_ids_np = self.input_ids_cpu.numpy()
self.positions_cpu = torch.zeros(self.max_num_tokens,
dtype=torch.int32,
device="cpu")
self.positions_np = self.positions_cpu.numpy()
self.slot_mapping_cpu = torch.zeros(self.max_num_tokens,
dtype=torch.int64,
device="cpu")
self.slot_mapping_np = self.slot_mapping_cpu.numpy()
padded_max_num_blocks_per_req = _get_padded_number(
self.max_num_blocks_per_req, NUM_KV_PAGES_PER_BLOCK)
self.block_table_cpu = torch.zeros(
(self.max_num_tokens, padded_max_num_blocks_per_req),
dtype=self.input_batch.block_table.get_cpu_tensor().dtype,
device="cpu")
self.query_start_loc_cpu = torch.zeros(self.max_num_tokens + 1,
dtype=torch.int32,
device="cpu",
pin_memory=self.pin_memory)
self.query_start_loc_np = self.query_start_loc_cpu.numpy()
self.seq_lens_cpu = torch.zeros(self.max_num_tokens,
dtype=torch.int32,
device="cpu",
pin_memory=self.pin_memory)
self.seq_lens_np = self.seq_lens_cpu.numpy()
# Range tensor with values [0 .. self.max_num_tokens - 1].
# Used to initialize positions / context_lens / seq_lens
self.arange_np = np.arange(self.max_num_tokens, dtype=np.int32)
self.num_tokens_paddings = _get_paddings(
min_token_size=16,
max_token_size=self.max_num_tokens,
padding_gap=envs.VLLM_TPU_BUCKET_PADDING_GAP)
def _update_num_xla_graphs(self, case_str):
check_comp = self.check_recompilation and not self.enforce_eager
if not check_comp:
return
total_cached_graphs = xr.get_num_cached_compilation_graph()
new_compiled_graphs = total_cached_graphs - self.num_xla_graphs
if new_compiled_graphs == 0:
return
logger.info("Add new %d compiled XLA graphs due to %s",
new_compiled_graphs, case_str)
self.num_xla_graphs += new_compiled_graphs
def _verify_num_xla_graphs(self, case_str):
check_comp = self.check_recompilation and not self.enforce_eager
if not check_comp:
return
curr_cached_graph = xr.get_num_cached_compilation_graph()
assert self.num_xla_graphs == curr_cached_graph, (
"Recompilation after warm up is detected during {}."
" num_xla_graphs = {} curr_cached_graph = {}".format(
case_str, self.num_xla_graphs, curr_cached_graph))
def _update_states(self, scheduler_output: "SchedulerOutput") -> bool:
"""Update the cached states and the persistent batch with the scheduler
output.
The updated states are used by the `_prepare_inputs` function to create
the input GPU tensors for the model.
Returns:
True if there is a new/resumed/paused/finished request.
If False, we can skip copying SamplingMetadata to the GPU.
"""
# Remove finished requests from the cached states.
for req_id in scheduler_output.finished_req_ids:
self.requests.pop(req_id, None)
self.encoder_cache.pop(req_id, None)
# Remove the finished requests from the persistent batch.
# NOTE(woosuk): There could be an edge case where finished_req_ids and
# scheduled_req_ids overlap. This happens when a request is aborted and
# then resubmitted with the same ID. In this case, we treat them as two
# distinct requests - clearing the cached states for the first request
# and handling the second as a new request.
removed_req_indices: list[int] = []
for req_id in scheduler_output.finished_req_ids:
req_index = self.input_batch.remove_request(req_id)
if req_index is not None:
removed_req_indices.append(req_index)
# Free the cached encoder outputs.
for req_id, input_id in scheduler_output.free_encoder_input_ids:
encoder_outputs = self.encoder_cache.get(req_id)
if encoder_outputs is not None:
encoder_outputs.pop(input_id, None)
if not encoder_outputs:
self.encoder_cache.pop(req_id, None)
# Remove the unscheduled requests from the persistent batch.
# NOTE(woosuk): The unscheduled requests are either preempted requests
# or running requests that are not scheduled in this step. We remove
# them from the persistent batch but keep their cached states since
# they will be scheduled again sometime in the future.
scheduled_req_ids = scheduler_output.num_scheduled_tokens.keys()
cached_req_ids = self.input_batch.req_id_to_index.keys()
unscheduled_req_ids = cached_req_ids - scheduled_req_ids
# NOTE(woosuk): The persistent batch optimization assumes that
# consecutive batches contain mostly the same requests. If batches
# have low request overlap (e.g., alternating between two distinct
# sets of requests), this optimization becomes very inefficient.
for req_id in unscheduled_req_ids:
req_index = self.input_batch.remove_request(req_id)
assert req_index is not None
removed_req_indices.append(req_index)
req_ids_to_add: list[str] = []
# Add new requests to the cached states.
for new_req_data in scheduler_output.scheduled_new_reqs:
req_id = new_req_data.req_id
sampling_params = new_req_data.sampling_params
if sampling_params.sampling_type == SamplingType.RANDOM_SEED:
generator = torch.Generator(device=self.device)
generator.manual_seed(sampling_params.seed)
else:
generator = None
self.requests[req_id] = CachedRequestState(
req_id=req_id,
prompt_token_ids=new_req_data.prompt_token_ids,
prompt=new_req_data.prompt,
mm_inputs=new_req_data.mm_inputs,
mm_positions=new_req_data.mm_positions,
sampling_params=sampling_params,
generator=generator,
block_ids=new_req_data.block_ids,
num_computed_tokens=new_req_data.num_computed_tokens,
output_token_ids=[],
lora_request=new_req_data.lora_request,
)
req_ids_to_add.append(req_id)
# Update the states of the running/resumed requests.
for req_data in scheduler_output.scheduled_cached_reqs:
req_id = req_data.req_id
req_state = self.requests[req_id]
# Update the cached states.
req_state.num_computed_tokens = req_data.num_computed_tokens
if not req_data.resumed_from_preemption:
# Append the new blocks to the existing block IDs.
req_state.block_ids.extend(req_data.new_block_ids)
else:
# The request is resumed from preemption.
# Replace the existing block IDs with the new ones.
req_state.block_ids = req_data.new_block_ids
req_index = self.input_batch.req_id_to_index.get(req_id)
if req_index is None:
# The request is not in the persistent batch.
# The request was either preempted and resumed later, or was not
# scheduled in the previous step and needs to be added again.
req_ids_to_add.append(req_id)
continue
# Update the persistent batch.
self.input_batch.num_computed_tokens_cpu[req_index] = (
req_data.num_computed_tokens)
self.input_batch.block_table.append_row(req_data.new_block_ids,
req_index)
# Add the new or resumed requests to the persistent batch.
# The smaller empty indices are filled first.
removed_req_indices = sorted(removed_req_indices, reverse=True)
for req_id in req_ids_to_add:
req_state = self.requests[req_id]
if removed_req_indices:
# Fill the empty index.
req_index = removed_req_indices.pop()
else:
# Append to the end.
req_index = None
self.input_batch.add_request(req_state, req_index)
# Condense the batched states if there are empty indices.
if removed_req_indices:
self.input_batch.condense(removed_req_indices)
return len(unscheduled_req_ids) > 0 or len(req_ids_to_add) > 0
def get_model(self) -> nn.Module:
assert self.model is not None
return self.model
def get_kv_cache_spec(self) -> dict[str, KVCacheSpec]:
"""
Generates the KVCacheSpec by parsing the kv cache format from each
Attention module in the static forward context.
Returns:
KVCacheSpec: A dictionary mapping layer names to their KV cache
format. Layers that do not need KV cache are not included.
"""
forward_ctx = self.vllm_config.compilation_config.static_forward_context
block_size = self.vllm_config.cache_config.block_size
kv_cache_spec: dict[str, KVCacheSpec] = {}
for layer_name, attn_module in forward_ctx.items():
# TODO: Support other attention modules, e.g., sliding window,
# cross-attention, MLA.
assert isinstance(attn_module, Attention)
if attn_module.attn_type == AttentionType.DECODER:
kv_cache_spec[layer_name] = FullAttentionSpec(
block_size=block_size,
num_kv_heads=attn_module.num_kv_heads,
head_size=attn_module.head_size,
dtype=attn_module.dtype,
use_mla=False,
)
elif attn_module.attn_type in (AttentionType.ENCODER,
AttentionType.ENCODER_ONLY):
# encoder-only attention does not need KV cache.
continue
elif attn_module.attn_type == AttentionType.ENCODER_DECODER:
raise NotImplementedError
else:
raise ValueError(
f"Unknown attention type: {attn_module.attn_type}")
return kv_cache_spec
def _prepare_inputs(self, scheduler_output: "SchedulerOutput"):
total_num_scheduled_tokens = scheduler_output.total_num_scheduled_tokens
assert total_num_scheduled_tokens > 0
num_reqs = self.input_batch.num_reqs
assert num_reqs > 0
# Get the number of scheduled tokens for each request.
num_scheduled_tokens_per_req = []
max_num_scheduled_tokens_all_reqs = 0
for req_id in self.input_batch.req_ids[:num_reqs]:
assert req_id is not None
num_tokens = scheduler_output.num_scheduled_tokens[req_id]
num_scheduled_tokens_per_req.append(num_tokens)
max_num_scheduled_tokens_all_reqs = max(
max_num_scheduled_tokens_all_reqs, num_tokens)
num_scheduled_tokens_per_req = np.array(num_scheduled_tokens_per_req,
dtype=np.int32)
assert max_num_scheduled_tokens_all_reqs > 0
# Get request indices.
# E.g., [2, 5, 3] -> [0, 0, 1, 1, 1, 1, 1, 2, 2, 2]
# For each scheduled token, what are the corresponding req index.
req_indices = np.repeat(self.arange_np[:num_reqs],
num_scheduled_tokens_per_req)
# Get batched arange.
# E.g., [2, 5, 3] -> [0, 1, 0, 1, 2, 3, 4, 0, 1, 2]
# For each scheduled token, what is its position in corresponding req.
arange = np.concatenate(
[self.arange_np[:n] for n in num_scheduled_tokens_per_req])
# Get positions.
positions_np = self.positions_np[:total_num_scheduled_tokens]
np.add(self.input_batch.num_computed_tokens_cpu[req_indices],
arange,
out=positions_np)
# Get token indices.
# E.g., [0, 1, 0, 1, 2, 3, 4, 0, 1, 2]
# -> [0, 1, M, M + 1, M + 2, M + 3, M + 4, 2 * M, 2 * M + 1, 2 * M + 2]
# where M is the max_model_len.
token_indices = (positions_np +
req_indices * self.input_batch.token_ids_cpu.shape[1])
# NOTE(woosuk): We use torch.index_select instead of np.take here
# because torch.index_select is much faster than np.take for large
# tensors.
torch.index_select(self.input_batch.token_ids_cpu_tensor.flatten(),
0,
torch.from_numpy(token_indices),
out=self.input_ids_cpu[:total_num_scheduled_tokens])
# Calculate the slot mapping.
# E.g., [0, 1, 0, 1, 2, 3, 4, 0, 1, 2]
# -> [0, 0, K, K, K + 1, K + 1, K + 2, 2 * K, 2 * K, 2 * K + 1]
# where K is the max_num_blocks_per_req and the block size is 2.
# NOTE(woosuk): We can't simply use `token_indices // block_size` here
# because M (max_model_len) is not necessarily divisible by block_size.
# req_indices: # E.g., [2, 5, 3] -> [0, 0, 1, 1, 1, 1, 1, 2, 2, 2]
block_table_indices = (req_indices * self.max_num_blocks_per_req +
positions_np // self.block_size)
# NOTE(woosuk): We use torch.index_select instead of np.take here
# because torch.index_select is much faster than np.take for large
# tensors.
block_table_cpu = self.input_batch.block_table.get_cpu_tensor()
block_numbers = block_table_cpu.flatten()[block_table_indices].numpy()
block_offsets = positions_np % self.block_size
np.add(block_numbers * self.block_size,
block_offsets,
out=self.slot_mapping_np[:total_num_scheduled_tokens])
# Prepare the attention metadata.
self.query_start_loc_np[0] = 0
np.cumsum(num_scheduled_tokens_per_req,
out=self.query_start_loc_np[1:num_reqs + 1])
self.query_start_loc_np[num_reqs + 1:] = 1
self.seq_lens_np[:num_reqs] = (
self.input_batch.num_computed_tokens_cpu[:num_reqs] +
num_scheduled_tokens_per_req)
# Do the padding and copy the tensors to the TPU.
padded_total_num_scheduled_tokens = _get_padded_token_len(
self.num_tokens_paddings, total_num_scheduled_tokens)
# Zero out to avoid spurious values from prev iteration (last cp chunk)
self.input_ids_cpu[
total_num_scheduled_tokens:padded_total_num_scheduled_tokens] = 0
self.input_ids = self.input_ids_cpu[:
padded_total_num_scheduled_tokens].to(
self.device)
self.position_ids = self.positions_cpu[:
padded_total_num_scheduled_tokens].to(
self.device)
self.slot_mapping_cpu[total_num_scheduled_tokens:] = _PAD_SLOT_ID
slot_mapping = self.slot_mapping_cpu[:
padded_total_num_scheduled_tokens].to(
self.device)
block_tables = self.block_table_cpu[:self.max_num_reqs]
block_tables[:num_reqs, :self.max_num_blocks_per_req] = (
self.input_batch.block_table.get_cpu_tensor()[:num_reqs])
block_tables = block_tables.to(self.device)
query_start_loc = self.query_start_loc_cpu[:self.max_num_reqs + 1].to(
self.device)
seq_lens = self.seq_lens_cpu[:self.max_num_reqs].to(self.device)
attn_metadata = PallasMetadata(
slot_mapping=slot_mapping,
block_tables=block_tables,
context_lens=seq_lens,
query_start_loc=query_start_loc,
num_seqs=torch.tensor([num_reqs],
dtype=torch.int32,
device=self.device),
)
# NOTE(woosuk): Due to chunked prefills, there can be at most 1 partial
# request in the batch. While we should not sample any token from this
# partial request, we do so for simplicity. We will ignore the sampled
# token from the partial request.
# TODO: Support prompt logprobs.
padded_num_reqs = _get_padded_num_reqs_with_upper_limit(
num_reqs, self.max_num_reqs)
# Indices at which we sample (positions of last token in the sequence).
# Padded to avoid recompiling when `num_reqs` varies.
logits_indices = self.query_start_loc_cpu[1:padded_num_reqs + 1] - 1
logits_indices = logits_indices.to(self.device)
return attn_metadata, logits_indices
def _execute_encoder(self, scheduler_output: "SchedulerOutput"):
scheduled_encoder_inputs = scheduler_output.scheduled_encoder_inputs
if not scheduled_encoder_inputs:
return
# Batch the multi-modal inputs.
mm_inputs: list[MultiModalKwargs] = []
req_input_ids: list[tuple[str, int]] = []
for req_id, encoder_input_ids in scheduled_encoder_inputs.items():
req_state = self.requests[req_id]
for input_id in encoder_input_ids:
mm_inputs.append(req_state.mm_inputs[input_id])
req_input_ids.append((req_id, input_id))
# Batch mm inputs as much as we can: if a request in the batch has
# multiple modalities or a different modality than the previous one,
# we process it separately to preserve item order.
# FIXME(ywang96): This is a hacky way to deal with multiple modalities
# in the same batch while still being able to benefit from batching
# multimodal inputs. The proper solution should be reordering the
# encoder outputs.
grouped_mm_inputs_list = group_mm_inputs_by_modality(mm_inputs)
encoder_outputs = []
for grouped_mm_inputs in grouped_mm_inputs_list:
batched_mm_inputs = MultiModalKwargs.batch(grouped_mm_inputs)
batched_mm_inputs = MultiModalKwargs.as_kwargs(batched_mm_inputs,
device=self.device)
# Run the encoder.
# `curr_group_outputs` is either of the following:
# 1. A tensor of shape (num_items, feature_size, hidden_size)
# in case feature_size is fixed across all multimodal items.
# 2. A list or tuple (length: num_items) of tensors, each of shape
# (feature_size, hidden_size) in case the feature size is dynamic
# depending on the input multimodal items.
curr_group_outputs = self.model.get_multimodal_embeddings(
**batched_mm_inputs)
sanity_check_mm_encoder_outputs(
curr_group_outputs,
expected_num_items=len(grouped_mm_inputs),
)
for output in curr_group_outputs:
encoder_outputs.append(output)
# Cache the encoder outputs.
for (req_id, input_id), output in zip(req_input_ids, encoder_outputs):
if req_id not in self.encoder_cache:
self.encoder_cache[req_id] = {}
self.encoder_cache[req_id][input_id] = output
def _gather_encoder_outputs(
self,
scheduler_output: "SchedulerOutput",
) -> list[torch.Tensor]:
encoder_outputs: list[torch.Tensor] = []
for req_id in self.input_batch.req_ids:
num_scheduled_tokens = scheduler_output.num_scheduled_tokens[
req_id]
req_state = self.requests[req_id]
num_computed_tokens = req_state.num_computed_tokens
mm_positions = req_state.mm_positions
for i, pos_info in enumerate(mm_positions):
start_pos = pos_info["offset"]
num_encoder_tokens = pos_info["length"]
# The encoder output is needed if the two ranges overlap:
# [num_computed_tokens,
# num_computed_tokens + num_scheduled_tokens) and
# [start_pos, start_pos + num_encoder_tokens)
if start_pos >= num_computed_tokens + num_scheduled_tokens:
# The encoder output is not needed in this step.
break
if start_pos + num_encoder_tokens <= num_computed_tokens:
# The encoder output is already processed and stored
# in the decoder's KV cache.
continue
start_idx = max(num_computed_tokens - start_pos, 0)
end_idx = min(
num_computed_tokens - start_pos + num_scheduled_tokens,
num_encoder_tokens)
assert start_idx < end_idx
assert req_id in self.encoder_cache
assert i in self.encoder_cache[req_id]
encoder_output = self.encoder_cache[req_id][i]
encoder_outputs.append(encoder_output[start_idx:end_idx])
return encoder_outputs
@torch.no_grad()
def execute_model(
self,
scheduler_output: "SchedulerOutput",
intermediate_tensors: Optional[IntermediateTensors] = None,
) -> ModelRunnerOutput:
# Update cached state
self._update_states(scheduler_output)
if not scheduler_output.total_num_scheduled_tokens:
# Return empty ModelRunnerOuptut if there's no work to do.
return EMPTY_MODEL_RUNNER_OUTPUT
if self.is_multimodal_model:
# Run the multimodal encoder if any.
self._execute_encoder(scheduler_output)
encoder_outputs = self._gather_encoder_outputs(scheduler_output)
else:
encoder_outputs = []
# Prepare inputs
attn_metadata, logits_indices = self._prepare_inputs(scheduler_output)
if self.is_multimodal_model:
# NOTE(woosuk): To unify token ids and soft tokens (vision
# embeddings), we always use embeddings (rather than token ids)
# as input to the multimodal model, even when the input is text.
if encoder_outputs:
inputs_embeds = self.model.get_input_embeddings(
self.input_ids, encoder_outputs)
else:
inputs_embeds = self.model.get_input_embeddings(self.input_ids)
input_ids = None
else:
# For text-only models, we use token ids as input.
# While it is possible to use embeddings as input just like the
# multimodal models, it is not desirable for performance since
# then the embedding layer is not included in the CUDA graph.
input_ids = self.input_ids
inputs_embeds = None
num_reqs = self.input_batch.num_reqs
# NOTE (NickLucche) here we sync with TPU: sampling params tensors
# are copied to device in chunks of pre-compiled padded shape to
# avoid recompilations.
tpu_sampling_metadata = TPUSupportedSamplingMetadata.\
from_input_batch(self.input_batch, logits_indices)
# Run the decoder
with set_forward_context(attn_metadata, self.vllm_config):
hidden_states = self.model(
input_ids=input_ids,
positions=self.position_ids,
kv_caches=self.kv_caches,
inputs_embeds=inputs_embeds,
)
selected_token_ids = self.model.sample_from_hidden(
hidden_states, tpu_sampling_metadata)
# Remove padding on cpu and keep dynamic op outside of xla graph.
selected_token_ids = selected_token_ids.cpu()[:num_reqs]
# Update the cache state concurrently. Code above will not block until
# we use `selected_token_ids`. Add mark_step if post-processing changes
request_seq_lens: list[tuple[int, CachedRequestState, int]] = []
discard_sampled_tokens_req_indices = []
for i, req_id in zip(range(num_reqs), self.input_batch.req_ids):
assert req_id is not None
req_state = self.requests[req_id]
seq_len = (req_state.num_computed_tokens +
scheduler_output.num_scheduled_tokens[req_id])
if seq_len >= req_state.num_tokens:
request_seq_lens.append((i, req_state, seq_len))
else:
# Ignore the sampled token from the partial request.
# Rewind the generator state as if the token was not sampled.
generator = self.input_batch.generators.get(i)
if generator is not None:
# This relies on cuda-specific torch-internal impl details
generator.set_offset(generator.get_offset() - 4)
# Record the index of the request that should not be sampled,
# so that we could clear the sampled tokens before returning.
discard_sampled_tokens_req_indices.append(i)
assert all(
req_id is not None for req_id in
self.input_batch.req_ids[:num_reqs]), "req_ids contains None"
req_ids = cast(list[str], self.input_batch.req_ids[:num_reqs])
prompt_logprobs_dict: dict[str, Optional[LogprobsTensors]] = {}
for req_id in self.input_batch.req_ids[:num_reqs]:
prompt_logprobs_dict[req_id] = None
max_gen_len = selected_token_ids.shape[-1]
if max_gen_len == 1:
valid_sampled_token_ids = selected_token_ids.tolist()
# Mask out the sampled tokens that should not be sampled.
# TODO: Keep in sync with gpu_model_runner.py, in particular
# the "else" case here
for i in discard_sampled_tokens_req_indices:
valid_sampled_token_ids[i].clear()
# Append sampled tokens
for i, req_state, seq_len in request_seq_lens:
token_id = valid_sampled_token_ids[i][0]
self.input_batch.token_ids_cpu[i, seq_len] = token_id
req_state.output_token_ids.append(token_id)
self.input_batch.num_tokens[i] += 1
else:
valid_mask = selected_token_ids != INVALID_TOKEN_ID
gen_lens = valid_mask.sum(dim=1).tolist()
valid_sampled_token_ids = [
seq.tolist()
for seq in selected_token_ids[valid_mask].split(gen_lens)
]
self.input_batch.num_tokens[:num_reqs] += gen_lens
for i, req_state, seq_len in request_seq_lens:
target_slice = slice(seq_len - gen_lens[i] + 1, seq_len + 1)
self.input_batch.token_ids_cpu[
i, target_slice] = valid_sampled_token_ids[i]
req_state.output_token_ids.extend(valid_sampled_token_ids[i])
model_runner_output = ModelRunnerOutput(
req_ids=req_ids,
req_id_to_index=self.input_batch.req_id_to_index,
sampled_token_ids=valid_sampled_token_ids,
spec_token_ids=None,
logprobs=None,
prompt_logprobs_dict=prompt_logprobs_dict,
)
# Check there are no new graphs compiled - all the graphs should be
# captured and compiled during warm up.
self._verify_num_xla_graphs("execute_model")
return model_runner_output
def load_model(self) -> None:
self.device = self.device_config.device
# NOTE(woosuk): While the executor assigns the TP ranks to the worker
# process, the ranks can be different from the ranks internally assigned
# by the xm runtime. Therefore, there is a mismatch in the rank
# assignment between the gloo (cpu) runtime and the xm (tpu) runtime.
# This is not a problem in linear layers because all-reduce is
# rank-agnostic. However, it matters for all-gather as the ranks
# determine the order of concatenating the output tensors.
# As a workaround, we use the xm's rank assignment only when loading
# the embedding weights.
xm_tp_rank = xr.global_ordinal()
with patch(
"vllm.model_executor.layers.vocab_parallel_embedding."
"get_tensor_model_parallel_rank",
return_value=xm_tp_rank):
model = get_model(vllm_config=self.vllm_config)
model = model.eval()
xm.mark_step()
xm.wait_device_ops()
model = ModelWrapperV1(model)
self.model = torch.compile(model,
backend="openxla",
fullgraph=True,
dynamic=False)
@torch.no_grad()
def _dummy_run(self, kv_caches, num_tokens: int) -> None:
if self.is_multimodal_model:
input_ids = None
inputs_embeds = torch.zeros((num_tokens, self.hidden_size),
dtype=self.dtype,
device=self.device)
else:
input_ids = torch.zeros((num_tokens),
dtype=torch.int32,
device=self.device)
inputs_embeds = None
actual_num_reqs = min(num_tokens, self.max_num_reqs)
position_ids = torch.zeros(num_tokens,
dtype=torch.int32,
device=self.device)
slot_mapping = torch.zeros(num_tokens,
dtype=torch.int64,
device=self.device)
block_tables = torch.zeros(
(self.max_num_reqs, self.block_table_cpu.shape[1]),
dtype=torch.int32,
device=self.device)
query_lens = [1] * self.max_num_reqs
query_start_loc = torch.cumsum(torch.tensor([0] + query_lens,
dtype=torch.int32),
dim=0,
dtype=torch.int32).to(self.device)
context_lens = torch.ones((self.max_num_reqs, ),
dtype=torch.int32,
device=self.device)
num_seqs = torch.tensor([actual_num_reqs],
dtype=torch.int32,
device=self.device)
attn_metadata = PallasMetadata(
slot_mapping=slot_mapping,
block_tables=block_tables,
context_lens=context_lens,
query_start_loc=query_start_loc,
num_seqs=num_seqs,
)
if self.is_multimodal_model:
torch._dynamo.mark_dynamic(inputs_embeds, 0)
else:
torch._dynamo.mark_dynamic(input_ids, 0)
torch._dynamo.mark_dynamic(position_ids, 0)
torch._dynamo.mark_dynamic(attn_metadata.slot_mapping, 0)
with set_forward_context(attn_metadata, self.vllm_config, 0):
out = self.model(input_ids=input_ids,
positions=position_ids,
kv_caches=kv_caches,
inputs_embeds=inputs_embeds)
self._hidden_states_dtype = out.dtype
def capture_model(self) -> None:
"""Compile the model."""
logger.info("Compiling the model with different input shapes.")
start = time.perf_counter()
for num_tokens in self.num_tokens_paddings:
logger.info(" -- num_tokens: %d", num_tokens)
self._dummy_run(self.kv_caches, num_tokens)
xm.mark_step()
xm.wait_device_ops()
end = time.perf_counter()
logger.info("Compilation finished in in %.2f [secs].", end - start)
self._update_num_xla_graphs("model")
logger.info("Compiling sampling with different input shapes.")
start = time.perf_counter()
hsize = self.model_config.get_hidden_size()
device = self.device
# Compile sampling step for different model+sampler outputs in bucketed
# n_tokens x max_num_reqs. Graph is really small so this is fine.
for num_tokens in self.num_tokens_paddings:
num_reqs_to_sample = MIN_NUM_SEQS
dummy_hidden = torch.randn((num_tokens, hsize),
device=device,
dtype=self._hidden_states_dtype)
# Compile for [8, 16, .., 128,.., `self.max_num_reqs`]
while True:
indices = torch.zeros(
num_reqs_to_sample,
dtype=torch.int32,
device=device,
)
xm.mark_step()
sampling_meta = TPUSupportedSamplingMetadata.\
from_input_batch(self.input_batch, indices)
logger.info(" -- num_tokens: %d, num_seqs: %d", num_tokens,
num_reqs_to_sample)
out = self.model.sample_from_hidden(dummy_hidden,
sampling_meta)
out = out.cpu()
if num_reqs_to_sample >= self.max_num_reqs:
break
# Make sure to compile the `max_num_reqs` upper-limit case
num_reqs_to_sample = _get_padded_num_reqs_with_upper_limit(
num_reqs_to_sample + 1, self.max_num_reqs)
xm.wait_device_ops()
end = time.perf_counter()
logger.info("Compilation finished in in %.2f [secs].", end - start)
self._update_num_xla_graphs("sampling")
def initialize_kv_cache(self, kv_cache_config: KVCacheConfig) -> None:
"""
Initialize KV cache based on `kv_cache_config`.
Args:
kv_cache_config: Configuration for the KV cache, including the KV
cache size of each layer
"""
if len(kv_cache_config.kv_cache_groups) > 1:
raise NotImplementedError(
"Hybrid models with more than one KV cache type are not "
"supported yet.")
kv_caches: dict[str, torch.Tensor] = {}
for kv_cache_group in kv_cache_config.kv_cache_groups:
kv_cache_spec = kv_cache_group.kv_cache_spec
for layer_name in kv_cache_group.layer_names:
tensor_config = kv_cache_config.tensors[layer_name]
assert tensor_config.size % kv_cache_spec.page_size_bytes == 0
num_blocks = tensor_config.size // kv_cache_spec.page_size_bytes
if isinstance(kv_cache_spec, FullAttentionSpec):
kv_cache_shape = PallasAttentionBackend.get_kv_cache_shape(
num_blocks, kv_cache_spec.block_size,
kv_cache_spec.num_kv_heads, kv_cache_spec.head_size)
dtype = kv_cache_spec.dtype
tpu_kv_cache = torch.zeros(kv_cache_shape,
dtype=dtype,
device=self.device)
kv_caches[layer_name] = tpu_kv_cache
else:
raise NotImplementedError
bind_kv_cache(
kv_caches,
self.vllm_config.compilation_config.static_forward_context,
self.kv_caches)
class ModelWrapperV1(nn.Module):
def __init__(self, model: nn.Module):
super().__init__()
self.model = model
self.sampler = TPUSampler()
def sample(
self, logits: torch.Tensor,
sampling_metadata: TPUSupportedSamplingMetadata) -> SamplerOutput:
sampler_out = self.sampler(logits, sampling_metadata)
return sampler_out
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
kv_caches: list[torch.Tensor],
inputs_embeds: Optional[torch.Tensor] = None,
) -> torch.Tensor:
"""Executes the forward pass of the model.
Args:
input_ids: The input token IDs of shape [num_tokens].
positions: The input position IDs of shape [num_tokens].
kv_caches: The key and value caches. They can be None during the
memory profiling at initialization.
inputs_embeds: The input embeddings of shape [num_tokens,
hidden_size]. It is used for multimodal models.
"""
hidden_states = self.model(
input_ids=input_ids,
positions=positions,
inputs_embeds=inputs_embeds,
)
return hidden_states
def sample_from_hidden(
self,
hidden_states: torch.Tensor,
sampling_metadata: TPUSupportedSamplingMetadata,
) -> torch.Tensor:
"""
Sample with xla-friendly function. This function is to be traced
separately from `forward` for lighter compilation overhead.
"""
# Tensor `sample_hidden_states` is of fixed pre-compiled size.
sample_hidden_states = \
hidden_states[sampling_metadata.indices_do_sample]
logits = self.compute_logits(sample_hidden_states)
# Optimized greedy sampling branch, tracing both paths in a single pass
# NOTE all_greedy is a scalar, this is just an optimized if/else.
out_tokens = torch.where(sampling_metadata.all_greedy,
torch.argmax(logits, dim=-1, keepdim=True),
self.sample(logits, sampling_metadata)\
.sampled_token_ids)
return out_tokens
def compute_logits(self,
hidden_states: torch.Tensor) -> Optional[torch.Tensor]:
# SamplingMetadata here for pruning output in LogitsProcessor, disabled
logits = self.model.compute_logits(hidden_states, None)
return logits
def get_multimodal_embeddings(self, *args, **kwargs):
return self.model.get_multimodal_embeddings(*args, **kwargs)
def get_input_embeddings(self, *args, **kwargs):
return self.model.get_input_embeddings(*args, **kwargs)
def _get_padded_number(n: int, multiple: int) -> int:
return ((n + multiple - 1) // multiple) * multiple
def _get_padded_num_reqs_with_upper_limit(x, upper_limit) -> int:
res = MIN_NUM_SEQS if x <= MIN_NUM_SEQS else 1 << (x - 1).bit_length()
return min(res, upper_limit)
def _get_paddings(min_token_size: int, max_token_size: int,
padding_gap: int) -> list[int]:
"""Generate a list of padding size, starting from min_token_size,
ending with a number that can cover max_token_size
If padding_gap == 0 then:
increase 2X each time (exponential)
else:
first increase the size to twice,
then increase the padding size by padding_gap.
"""
paddings = []
num = min_token_size
if padding_gap == 0:
logger.info("Using exponential paddings:")
while num <= max_token_size:
logger.info(" %d", num)
paddings.append(num)
num *= 2
else:
logger.info("Using incremental paddings:")
while num <= padding_gap:
logger.info(" %d", num)
paddings.append(num)
num *= 2
num //= 2
while num < max_token_size:
num += padding_gap
logger.info(" %d", num)
paddings.append(num)
return paddings
def _get_padded_token_len(paddings: list[int], x: int) -> int:
"""Return the first element in paddings list greater or equal to x.
"""
index = bisect.bisect_left(paddings, x)
assert index < len(paddings)
return paddings[index]