text-generation-inference/server/text_generation_server/models/flash_causal_lm.py
Nicolas Patry 7a48a84784
Using an enum for flash backens (paged/flashdecoding/flashinfer) (#2385)
* Using an enum for flash backens (paged/flashdecoding/flashinfer)

* Early exit on server too.

* Clippy.

* Fix clippy and fmt.
2024-08-09 16:41:17 +02:00

1795 lines
67 KiB
Python

from contextlib import nullcontext
import math
import os
import time
import torch
import torch.distributed
import numpy as np
from loguru import logger
from dataclasses import dataclass
from opentelemetry import trace
from transformers import (
PreTrainedTokenizerBase,
AutoConfig,
AutoTokenizer,
GenerationConfig,
)
from typing import Any, ContextManager, Iterable, Optional, Tuple, List, Type, Dict
from text_generation_server.adapters import AdapterBatchData, AdapterBatchMetadata
from huggingface_hub.constants import HUGGINGFACE_HUB_CACHE
from text_generation_server.utils.chunks import concat_text_chunks
from text_generation_server.utils.import_utils import SYSTEM
from text_generation_server.models import Model
from text_generation_server.utils.log import log_master
from text_generation_server.utils.tokens import batch_top_tokens
from text_generation_server.utils.speculate import get_speculate
from text_generation_server.utils import (
initialize_torch_distributed,
weight_files,
Weights,
)
from text_generation_server.models.types import (
Batch,
Tokens,
Generation,
GeneratedText,
)
from text_generation_server.pb import generate_pb2
from text_generation_server.models.globals import (
MEM_POOL,
ATTENTION,
BLOCK_SIZE,
CUDA_GRAPHS,
get_adapter_to_index,
)
from text_generation_server.layers.attention import Seqlen
from text_generation_server.utils import StoppingCriteria, HeterogeneousNextTokenChooser
from text_generation_server.utils.dist import MEMORY_FRACTION
from text_generation_server.utils.quantization import get_loader
from text_generation_server.utils.segments import SegmentConcatBuilder, find_segments
from text_generation_server.utils.import_utils import (
empty_cache,
synchronize,
get_free_memory,
)
tracer = trace.get_tracer(__name__)
# Will be set in init
SLIDING_WINDOW: Optional[int] = None
def set_sliding_window(sliding_window: int):
global SLIDING_WINDOW
SLIDING_WINDOW = sliding_window
def get_sliding_windows() -> int:
global SLIDING_WINDOW
return SLIDING_WINDOW
@dataclass
class FlashCausalLMBatch(Batch):
batch_id: int
requests: List[generate_pb2.Request]
# request id -> idx in list mapping
requests_idx_mapping: Dict[int, int]
# Decoder values
input_ids: torch.Tensor
position_ids: torch.Tensor
speculative_ids: Optional[torch.Tensor]
# Flash Attention values
# tensor of length b containing the cumulative sequence lengths of the sequences in the batch, only used in prefill
cu_seqlen_prefill: Optional[torch.Tensor]
# Prefill cache indices is used to slice into the kv tensor before caching it into the paged attention buffers
# as we only keep SLIDING_WINDOW values instead of the whole tensor
prefill_cache_indices: Optional[torch.Tensor]
# Paged Attention values
# Set when creating the batch
# CPU tensor of length b indicating the start of each sequence in slots
start_slots: torch.Tensor
# tensor of indices of the currently used slots, length = \sum_{i=0}^{b} s_i in prefill, length = b in decode
slot_indices: torch.Tensor
# list of length b of list of length s_i // block_size
block_tables: List[List[int]]
# tensor of size [b, max_total_seqlen // block_size] holding the paged attention block tables for all sequences
block_tables_tensor: torch.Tensor
# tensor of length \sum_{i=0}^{b} max_s_i holding the paged attention slots for all sequences
slots: torch.Tensor
max_seqlen: int
# Prefill metadata tensors to efficiently compute logprobs
prefill_head_indices: Optional[torch.Tensor]
prefill_next_token_indices: Optional[torch.tensor]
prefill_cu_outlens: Optional[List[int]]
# All tokens
all_input_ids: List[List[int]]
all_input_ids_tensor: torch.Tensor
# Lengths of all generations present in the batch
input_lengths: List[int]
input_lengths_tensor: torch.Tensor
prefix_offsets: List[Optional[int]]
read_offsets: List[Optional[int]]
# Generation helpers
next_token_chooser: HeterogeneousNextTokenChooser
stopping_criterias: List[StoppingCriteria]
top_n_tokens: List[int]
top_n_tokens_tensor: torch.Tensor
# Adapter metadata for each request
adapter_meta: AdapterBatchMetadata
# Number of blocks in this batch
num_blocks: int
# Maximum number of blocks
max_blocks: int
def to_pb(self) -> generate_pb2.CachedBatch:
return generate_pb2.CachedBatch(
id=self.batch_id,
request_ids=[r.id for r in self.requests],
size=len(self),
max_tokens=self.num_blocks * BLOCK_SIZE,
)
@classmethod
def batch_tokenized_inputs(
cls, requests: Iterable[generate_pb2.Request], tokenizer
):
batch_inputs = []
max_truncation = 0
for r in requests:
batch_inputs.append(concat_text_chunks(r.input_chunks.chunks))
max_truncation = max(max_truncation, r.truncate)
batch_tokenized_inputs = tokenizer(
batch_inputs, truncation=True, max_length=max_truncation
)["input_ids"]
return batch_tokenized_inputs
@classmethod
def from_tokenized(
cls,
pb: generate_pb2.Batch,
tokenizer: PreTrainedTokenizerBase,
batch_tokenized_inputs,
dtype: torch.dtype,
device: torch.device,
) -> "FlashCausalLMBatch":
sliding_window = get_sliding_windows()
position_ids = []
cu_seqlen_prefill = [0]
start_slots = []
slot_indices = []
prefill_cache_indices = []
input_lengths = []
prefix_offsets = []
read_offsets = []
all_input_ids = []
requests_idx_mapping = {}
all_prefill_logprobs = True
no_prefill_logprobs = True
prefill_head_indices = []
prefill_next_token_indices = []
prefill_cu_outlens = [0]
next_token_chooser_parameters = []
stopping_criterias = []
top_n_tokens = []
adapter_indices_list = []
adapter_set = set()
# Cumulative length
cumulative_length = 0
cumulative_max_length = 0
prefill_out_cumulative_length = 0
num_blocks = 0
max_seqlen = 0
max_length = 0
max_blocks = 0
block_tables = []
slots = []
# Parse batch
for i, (r, tokenized_input) in enumerate(
zip(pb.requests, batch_tokenized_inputs)
):
# request id -> idx in list mapping
requests_idx_mapping[r.id] = i
tokenized_input = tokenized_input[-r.truncate :]
if (
tokenized_input[0] == tokenizer.bos_token_id
and tokenized_input[1] == tokenizer.bos_token_id
):
tokenized_input = tokenized_input[1:]
input_length = len(tokenized_input)
input_lengths.append(input_length)
prefix_offsets.append(input_length - 5)
read_offsets.append(input_length)
all_input_ids.append(tokenized_input)
# Position ids
request_position_ids = torch.arange(0, input_length, dtype=torch.int32)
position_ids.append(request_position_ids)
# Add cumulative lengths of all previous inputs
cu_seqlen_prefill.append(cumulative_length + input_length)
next_token_chooser_parameters.append(r.parameters)
stopping_criteria = StoppingCriteria.from_pb(
r.stopping_parameters, tokenizer
)
max_new_tokens = stopping_criteria.max_new_tokens
stopping_criterias.append(stopping_criteria)
top_n_tokens.append(r.top_n_tokens)
ADAPTER_TO_INDEX = get_adapter_to_index()
adapter_index = ADAPTER_TO_INDEX.get(r.adapter_id, 0)
adapter_indices_list.append(torch.full((input_length,), adapter_index))
adapter_set.add(adapter_index)
# Paged attention
# Remove one as the first token des not have a past
speculative_length = get_speculate()
speculative_length = 0 if speculative_length is None else speculative_length
total_tokens = input_length + max_new_tokens - 1 + speculative_length
# blocks and slots can be empty (for example in warmup)
if not r.blocks:
needed_blocks = math.ceil(total_tokens / BLOCK_SIZE)
request_blocks = [
b for b in range(num_blocks, num_blocks + needed_blocks)
]
request_slots = [
s
for b in request_blocks
for s in range(b * BLOCK_SIZE, (b + 1) * BLOCK_SIZE)
]
else:
request_blocks = r.blocks
request_slots = r.slots
block_tables.append(request_blocks)
slots.extend(request_slots[:total_tokens])
num_blocks += len(request_blocks)
start_slots.append(cumulative_max_length)
request_slot_indices = torch.arange(
cumulative_max_length,
cumulative_max_length + input_length,
dtype=torch.int64,
)
slot_indices.append(request_slot_indices)
# Create tensor to slice into the kv tensor in prefill
if sliding_window is not None:
request_prefill_cache_indices = torch.arange(
cumulative_length + max(0, input_length - sliding_window),
cumulative_length + input_length,
dtype=torch.int64,
)
prefill_cache_indices.append(request_prefill_cache_indices)
all_prefill_logprobs = all_prefill_logprobs and r.prefill_logprobs
no_prefill_logprobs = no_prefill_logprobs and not r.prefill_logprobs
if r.prefill_logprobs:
prefill_head_indices.append(request_position_ids + cumulative_length)
prefill_next_token_indices.append(
prefill_out_cumulative_length + input_length - 1
)
prefill_cu_outlens.append(prefill_out_cumulative_length + input_length)
prefill_out_cumulative_length += input_length
else:
prefill_head_indices.append(
torch.tensor(
[cumulative_length + input_length - 1], dtype=torch.int32
)
)
prefill_next_token_indices.append(prefill_out_cumulative_length)
prefill_cu_outlens.append(prefill_out_cumulative_length + 1)
prefill_out_cumulative_length += 1
# Update
cumulative_length += input_length
cumulative_max_length += total_tokens
max_seqlen = max(max_seqlen, input_length)
max_blocks = max(max_blocks, len(request_blocks))
max_length = max(
max_length, input_length + max_new_tokens + speculative_length
)
adapter_indices = torch.cat(adapter_indices_list).to(
dtype=torch.int64, device=device
)
next_token_chooser = HeterogeneousNextTokenChooser.from_pb(
next_token_chooser_parameters, dtype, device, tokenizer
)
start_slots = torch.tensor(start_slots, dtype=torch.int64)
# Padded all_input_ids_tensor
all_input_ids_tensor = np.zeros(
(len(all_input_ids), max_length), dtype=np.int64
)
for i, input_ids in enumerate(all_input_ids):
all_input_ids_tensor[i, : len(input_ids)] = input_ids
# Create tensors on device
all_input_ids_tensor = torch.tensor(
all_input_ids_tensor, dtype=torch.int64, device=device
)
if len(pb.requests) > 1:
input_ids = np.concatenate(all_input_ids, dtype=np.int64)
position_ids = torch.cat(position_ids)
slot_indices = torch.cat(slot_indices)
if sliding_window is not None:
prefill_cache_indices = torch.cat(prefill_cache_indices)
else:
input_ids = all_input_ids[0]
position_ids = position_ids[0]
slot_indices = slot_indices[0]
if sliding_window is not None:
prefill_cache_indices = prefill_cache_indices[0]
cu_seqlen_prefill = torch.tensor(
cu_seqlen_prefill, device=device, dtype=torch.int32
)
position_ids = position_ids.to(device)
slot_indices = slot_indices.to(device)
prefill_cache_indices = (
prefill_cache_indices.to(device) if sliding_window is not None else None
)
input_ids = torch.tensor(input_ids, dtype=torch.int64, device=device)
input_lengths_tensor = torch.tensor(
input_lengths, dtype=torch.int32, device=device
)
adapter_segments, adapter_segment_indices = find_segments(adapter_indices)
adapter_segments = torch.tensor(
adapter_segments, dtype=torch.int32, device=device
)
if all_prefill_logprobs:
prefill_head_indices = None
prefill_next_token_indices = cu_seqlen_prefill[1:] - 1
elif no_prefill_logprobs:
prefill_head_indices = cu_seqlen_prefill[1:] - 1
prefill_next_token_indices = None
else:
prefill_head_indices = torch.tensor(
torch.cat(prefill_head_indices), dtype=torch.int64, device=device
)
prefill_next_token_indices = torch.tensor(
prefill_next_token_indices, dtype=torch.int64, device=device
)
top_n_tokens_tensor = torch.tensor(
top_n_tokens, device=device, dtype=torch.int64
)
slots = torch.tensor(slots, dtype=torch.int64, device=device)
block_tables_tensor = torch.zeros(
(len(block_tables), max_blocks), dtype=torch.int32, device="cpu"
)
for i, request_blocks in enumerate(block_tables):
block_tables_tensor[i, : len(request_blocks)] = torch.tensor(request_blocks)
block_tables_tensor = block_tables_tensor.to(device)
return cls(
batch_id=pb.id,
requests=pb.requests,
requests_idx_mapping=requests_idx_mapping,
input_ids=input_ids,
position_ids=position_ids,
cu_seqlen_prefill=cu_seqlen_prefill,
prefill_cache_indices=prefill_cache_indices,
start_slots=start_slots,
slot_indices=slot_indices,
block_tables=block_tables,
block_tables_tensor=block_tables_tensor,
slots=slots,
max_seqlen=max_seqlen,
prefill_head_indices=prefill_head_indices,
prefill_next_token_indices=prefill_next_token_indices,
prefill_cu_outlens=prefill_cu_outlens,
input_lengths=input_lengths,
input_lengths_tensor=input_lengths_tensor,
prefix_offsets=prefix_offsets,
read_offsets=read_offsets,
all_input_ids=all_input_ids,
all_input_ids_tensor=all_input_ids_tensor,
next_token_chooser=next_token_chooser,
stopping_criterias=stopping_criterias,
top_n_tokens=top_n_tokens,
top_n_tokens_tensor=top_n_tokens_tensor,
num_blocks=num_blocks,
max_blocks=max_blocks,
adapter_meta=AdapterBatchMetadata(
adapter_indices=adapter_indices,
adapter_set=adapter_set,
adapter_segments=adapter_segments,
segment_indices=adapter_segment_indices,
),
speculative_ids=None,
)
@classmethod
def from_pb(
cls,
pb: generate_pb2.Batch,
tokenizer: PreTrainedTokenizerBase,
dtype: torch.dtype,
device: torch.device,
) -> "FlashCausalLMBatch":
batch_tokenized_inputs = cls.batch_tokenized_inputs(pb.requests, tokenizer)
return cls.from_tokenized(pb, tokenizer, batch_tokenized_inputs, dtype, device)
@tracer.start_as_current_span("filter")
def filter(self, request_ids: List[int]) -> "FlashCausalLMBatch":
if len(request_ids) == 0:
raise ValueError("Batch must have at least one request")
# We assume that if len(requests) == len(self) then the requests are the same
if len(request_ids) == len(self):
return self
device = self.input_ids.device
# New values after filtering
requests_idx_mapping = {}
# Used to index into tensors
indices = []
# slots to keep after filtering
slot_filtering_indices = torch.zeros(
self.slots.shape[0], dtype=torch.bool, device=device
)
# Create on CPU to only move to GPU once instead of at every copy
slot_indices = torch.empty(len(request_ids), dtype=torch.int64)
max_seqlen = 0
requests = []
start_slots = []
block_tables = []
all_input_ids = []
input_lengths = []
prefix_offsets = []
read_offsets = []
stopping_criterias = []
top_n_tokens = []
adapter_set = set()
num_blocks = 0
max_blocks = 0
# Cumulative length
cumulative_max_length = 0
for i, request_id in enumerate(request_ids):
idx = self.requests_idx_mapping[request_id]
indices.append(idx)
requests_idx_mapping[request_id] = i
requests.append(self.requests[idx])
# Get length
request_input_length = self.input_lengths[idx]
max_seqlen = max(max_seqlen, request_input_length)
all_input_ids.append(self.all_input_ids[idx])
input_lengths.append(request_input_length)
prefix_offsets.append(self.prefix_offsets[idx])
read_offsets.append(self.read_offsets[idx])
stopping_criteria = self.stopping_criterias[idx]
stopping_criterias.append(stopping_criteria)
top_n_tokens.append(self.top_n_tokens[idx])
ADAPTER_TO_INDEX = get_adapter_to_index()
adapter_index = ADAPTER_TO_INDEX.get(self.requests[idx].adapter_id, 0)
adapter_set.add(adapter_index)
remaining_tokens = (
stopping_criteria.max_new_tokens - stopping_criteria.current_tokens
)
request_block_table = self.block_tables[idx]
num_blocks += len(request_block_table)
block_tables.append(request_block_table)
start_slots.append(cumulative_max_length)
# Copy to tensor (CPU)
slot_indices[i] = cumulative_max_length + request_input_length - 1
# Set slice
slot_filtering_indices[
self.start_slots[idx] : self.start_slots[idx]
+ request_input_length
+ remaining_tokens
- 1
] = True
cumulative_max_length += request_input_length + remaining_tokens - 1
max_blocks = max(max_blocks, len(request_block_table))
# Index into tensors
input_ids = self.input_ids[indices]
position_ids = self.position_ids[indices]
adapter_indices = self.adapter_meta.adapter_indices[indices]
all_input_ids_tensor = self.all_input_ids_tensor[indices]
block_tables_tensor = self.block_tables_tensor[indices]
input_lengths_tensor = self.input_lengths_tensor[indices]
slots = self.slots[slot_filtering_indices]
next_token_chooser = self.next_token_chooser.filter(indices)
top_n_tokens_tensor = self.top_n_tokens_tensor[indices]
speculative_ids = (
self.speculative_ids[indices] if self.speculative_ids is not None else None
)
start_slots = torch.tensor(start_slots, dtype=torch.int64)
# Move to GPU now that we have the whole tensor
slot_indices = slot_indices.to(device)
adapter_segments, adapter_segment_indices = find_segments(adapter_indices)
adapter_segments = torch.tensor(
adapter_segments, dtype=torch.int32, device=device
)
return type(self)(
batch_id=self.batch_id,
requests=requests,
requests_idx_mapping=requests_idx_mapping,
input_ids=input_ids,
position_ids=position_ids,
cu_seqlen_prefill=None,
prefill_cache_indices=None,
start_slots=start_slots,
slot_indices=slot_indices,
block_tables=block_tables,
block_tables_tensor=block_tables_tensor,
slots=slots,
max_seqlen=max_seqlen,
prefill_head_indices=None,
prefill_next_token_indices=None,
prefill_cu_outlens=None,
input_lengths=input_lengths,
input_lengths_tensor=input_lengths_tensor,
prefix_offsets=prefix_offsets,
read_offsets=read_offsets,
all_input_ids=all_input_ids,
all_input_ids_tensor=all_input_ids_tensor,
next_token_chooser=next_token_chooser,
stopping_criterias=stopping_criterias,
top_n_tokens=top_n_tokens,
top_n_tokens_tensor=top_n_tokens_tensor,
num_blocks=num_blocks,
max_blocks=max_blocks,
speculative_ids=speculative_ids,
adapter_meta=AdapterBatchMetadata(
adapter_indices=adapter_indices,
adapter_set=adapter_set,
adapter_segments=adapter_segments,
segment_indices=adapter_segment_indices,
),
)
@classmethod
@tracer.start_as_current_span("concatenate")
def concatenate(cls, batches: List["FlashCausalLMBatch"]) -> "FlashCausalLMBatch":
# Batch attributes
requests = []
requests_idx_mapping = {}
num_blocks = 0
total_batch_size = 0
total_slots = 0
max_blocks = 0
max_length = 0
max_seqlen = 0
for b in batches:
total_batch_size += len(b)
total_slots += len(b.slots)
num_blocks += b.num_blocks
speculative_length = (
b.speculative_ids.shape[1] if b.speculative_ids is not None else 0
)
max_blocks = max(max_blocks, b.max_blocks)
max_seqlen = max(max_seqlen, b.max_seqlen)
max_length = max(
max_length,
max(
input_length
+ stopping_criteria.max_new_tokens
+ speculative_length
- stopping_criteria.current_tokens
for input_length, stopping_criteria in zip(
b.input_lengths, b.stopping_criterias
)
),
)
input_ids = batches[0].input_ids.new_empty(total_batch_size)
position_ids = batches[0].position_ids.new_empty(total_batch_size)
slots = batches[0].slots.new_empty(total_slots)
slot_indices = batches[0].slot_indices.new_empty(total_batch_size)
input_lengths_tensor = batches[0].input_lengths_tensor.new_empty(
total_batch_size
)
block_tables_tensor = batches[0].block_tables_tensor.new_zeros(
(total_batch_size, max_blocks)
)
all_input_ids_tensor = batches[0].all_input_ids_tensor.new_zeros(
(total_batch_size, max_length)
)
top_n_tokens_tensor = batches[0].top_n_tokens_tensor.new_zeros(
total_batch_size,
)
total_indices_size = sum(
b.adapter_meta.adapter_indices.shape[0] for b in batches
)
adapter_indices = batches[0].adapter_meta.adapter_indices.new_empty(
total_indices_size
)
adapter_set = set()
adapter_segment_builder = SegmentConcatBuilder()
start_slots = []
block_tables = []
all_input_ids = []
input_lengths = []
prefix_offsets = []
read_offsets = []
next_token_chooser_parameters = []
fsm_grammar_states = []
stopping_criterias = []
top_n_tokens = []
# Cumulative length
cumulative_batch_size = 0
cumulative_slots = 0
cumulative_adapter_indices_size = 0
for i, batch in enumerate(batches):
requests.extend(batch.requests)
if i == 0:
requests_idx_mapping = batch.requests_idx_mapping
else:
# We need to offset the mapping for each batch by the cumulative batch size
for k, v in batch.requests_idx_mapping.items():
requests_idx_mapping[k] = v + cumulative_batch_size
start_index = cumulative_batch_size
end_index = cumulative_batch_size + len(batch)
slots_start_index = cumulative_slots
slots_end_index = cumulative_slots + len(batch.slots)
# Copy tensors (GPU)
input_ids[start_index:end_index] = batch.input_ids
position_ids[start_index:end_index] = batch.position_ids
slot_indices[start_index:end_index] = batch.slot_indices + cumulative_slots
input_lengths_tensor[start_index:end_index] = batch.input_lengths_tensor
top_n_tokens_tensor[start_index:end_index] = batch.top_n_tokens_tensor
slots[slots_start_index:slots_end_index] = batch.slots
# Copy over adapter indices
adapter_start_index = cumulative_adapter_indices_size
adapter_end_index = (
cumulative_adapter_indices_size
+ batch.adapter_meta.adapter_indices.shape[0]
)
adapter_indices[adapter_start_index:adapter_end_index] = (
batch.adapter_meta.adapter_indices
)
cumulative_adapter_indices_size = adapter_end_index
adapter_set.update(batch.adapter_meta.adapter_set)
adapter_segment_builder.concat(
batch.adapter_meta.adapter_segments, batch.adapter_meta.segment_indices
)
all_input_ids_tensor[
start_index:end_index, : batch.all_input_ids_tensor.shape[1]
] = batch.all_input_ids_tensor[:, :max_length]
block_tables_tensor[
start_index:end_index, : batch.block_tables_tensor.shape[1]
] = batch.block_tables_tensor[:, :max_blocks]
start_slots.append(batch.start_slots + cumulative_slots)
block_tables.extend(batch.block_tables)
all_input_ids.extend(batch.all_input_ids)
input_lengths.extend(batch.input_lengths)
prefix_offsets.extend(batch.prefix_offsets)
read_offsets.extend(batch.read_offsets)
next_token_chooser_parameters.extend([r.parameters for r in batch.requests])
fsm_grammar_states.extend(batch.next_token_chooser.fsm_grammar_states)
stopping_criterias.extend(batch.stopping_criterias)
top_n_tokens.extend(batch.top_n_tokens)
# Update
cumulative_batch_size += len(batch)
cumulative_slots += len(batch.slots)
start_slots = torch.concat(start_slots)
next_token_chooser = HeterogeneousNextTokenChooser.from_pb(
next_token_chooser_parameters,
dtype=batches[0].next_token_chooser.dtype,
device=batches[0].next_token_chooser.device,
tokenizer=batches[0].next_token_chooser.tokenizer,
fsm_grammar_states=fsm_grammar_states,
)
speculative_ids = (
torch.cat([b.speculative_ids for b in batches], dim=0)
if batches[0].speculative_ids is not None
else None
)
adapter_segments, adapter_segment_indices = adapter_segment_builder.build()
return cls(
batch_id=batches[0].batch_id,
requests=requests,
requests_idx_mapping=requests_idx_mapping,
input_ids=input_ids,
position_ids=position_ids,
cu_seqlen_prefill=None,
prefill_cache_indices=None,
start_slots=start_slots,
slot_indices=slot_indices,
block_tables=block_tables,
block_tables_tensor=block_tables_tensor,
slots=slots,
max_seqlen=max_seqlen,
prefill_head_indices=None,
prefill_next_token_indices=None,
prefill_cu_outlens=None,
input_lengths=input_lengths,
input_lengths_tensor=input_lengths_tensor,
prefix_offsets=prefix_offsets,
read_offsets=read_offsets,
all_input_ids=all_input_ids,
all_input_ids_tensor=all_input_ids_tensor,
next_token_chooser=next_token_chooser,
stopping_criterias=stopping_criterias,
top_n_tokens=top_n_tokens,
top_n_tokens_tensor=top_n_tokens_tensor,
num_blocks=num_blocks,
max_blocks=max_blocks,
speculative_ids=speculative_ids,
adapter_meta=AdapterBatchMetadata(
adapter_indices=adapter_indices,
adapter_set=adapter_set,
adapter_segments=adapter_segments,
segment_indices=adapter_segment_indices,
),
)
def __len__(self):
return len(self.requests)
ADAPTER_LAYERS = [
"q_proj",
"k_proj",
"v_proj",
"o_proj",
"gate_proj",
"up_proj",
"down_proj",
]
ROW_PARALLEL = {"o_proj", "down_proj", "lm_head"}
class FlashCausalLM(Model):
def __init__(
self,
model_id: str,
model_class,
revision: Optional[str] = None,
quantize: Optional[str] = None,
speculator: Optional[str] = None,
dtype: Optional[torch.dtype] = None,
trust_remote_code: bool = False,
lora_adapter_ids: Optional[list] = [],
tokenizer_class: PreTrainedTokenizerBase = AutoTokenizer,
config_class: PreTrainedTokenizerBase = AutoConfig,
default_dtype=torch.float16,
aliases=None,
# Used for Santacoder override of config
num_kv_heads: Optional[int] = None,
# Deepseek V2 uses different QK and V dims.
head_size: Optional[int] = None,
skip_special_tokens: bool = True,
):
self.process_group, rank, world_size = initialize_torch_distributed()
if torch.cuda.is_available():
device = torch.device(f"cuda:{rank}")
dtype = default_dtype if dtype is None else dtype
elif SYSTEM == "ipex":
if hasattr(torch, "xpu") and torch.xpu.is_available():
device = torch.device(f"xpu:{rank}")
dtype = default_dtype if dtype is None else dtype
else:
device = torch.device("cpu")
# Float16 doesn't exist on target.
dtype = torch.bfloat16 if dtype is None else dtype
else:
raise NotImplementedError(f"{model_class} is only available on GPU")
tokenizer = tokenizer_class.from_pretrained(
model_id,
revision=revision,
padding_side="left",
truncation_side="left",
trust_remote_code=trust_remote_code,
)
try:
generation_config = GenerationConfig.from_pretrained(
model_id, revision=revision, trust_remote_code=trust_remote_code
)
if isinstance(generation_config.eos_token_id, (list, set)):
# TODO Huge hack
tokenizer._eos_token_ids = set(generation_config.eos_token_id)
except Exception:
pass
config = config_class.from_pretrained(
model_id, revision=revision, trust_remote_code=trust_remote_code
)
config.quantize = quantize
config.speculator = speculator
torch.distributed.barrier(group=self.process_group)
weights_loader = get_loader(quantize, model_id, revision)
filenames = weight_files(model_id, revision=revision, extension=".safetensors")
weights = Weights(
filenames,
device,
dtype,
process_group=self.process_group,
aliases=aliases,
weights_loader=weights_loader,
)
prefix = ""
model = model_class(prefix, config, weights)
torch.distributed.barrier(group=self.process_group)
# VLM models define the config we care about in their text_config
text_config = getattr(config, "text_config", None)
if text_config is not None:
config = text_config
if getattr(config, "sliding_window", None) is not None:
set_sliding_window(config.sliding_window)
else:
config.sliding_window = None
self.num_layers = config.num_hidden_layers
self.num_heads = config.num_attention_heads
# Validation is done in the model itself
if num_kv_heads is None:
num_kv_heads = getattr(config, "num_key_value_heads", None)
# GPT-2 workaround
if num_kv_heads is None:
num_kv_heads = getattr(config, "n_head", None)
if num_kv_heads is None:
raise ValueError("Cannot get the number of key/value heads")
self.num_kv_heads = (
num_kv_heads // self.process_group.size()
if num_kv_heads > 1
else num_kv_heads
)
assert self.num_kv_heads > 0
if head_size is None:
# Some models use GQA and different sizes for o_proj
# and q_proj, that allows for that.
if hasattr(config, "head_dim"):
self.head_size = config.head_dim
else:
self.head_size = config.hidden_size // config.num_attention_heads
else:
self.head_size = head_size
self.cuda_graphs = {}
self.kv_cache = []
if ATTENTION == "flashinfer":
from text_generation_server.layers.attention.flash_infer import (
create_prefill_state,
create_decode_state,
)
self.prefill_state = create_prefill_state(device=device)
if not CUDA_GRAPHS:
self.decode_state = create_decode_state(
device=device,
num_heads=self.num_heads,
num_kv_heads=self.num_kv_heads,
)
super().__init__(
model_id=model_id,
model=model,
tokenizer=tokenizer,
requires_padding=False,
dtype=dtype,
device=device,
rank=rank,
world_size=world_size,
sliding_window=config.sliding_window,
)
@property
def batch_type(self) -> Type[FlashCausalLMBatch]:
return FlashCausalLMBatch
def max_past(self) -> int:
return getattr(self.model, "max_past", None)
def init_kv_cache(
self,
num_blocks: int,
num_layers: int,
num_heads: int,
head_size: int,
dtype: torch.dtype,
device: torch.device,
):
self.kv_cache = []
empty_cache()
element_size = torch.tensor([], dtype=dtype).element_size()
if SYSTEM == "ipex" and device.type == "xpu":
x = 1
else:
x = BLOCK_SIZE // element_size
if ATTENTION in {"flashdecoding", "flashinfer"}:
self.kv_cache = [
(
torch.empty(
(num_blocks, BLOCK_SIZE, num_heads, head_size),
dtype=dtype,
device=device,
),
torch.empty(
(num_blocks, BLOCK_SIZE, num_heads, head_size),
dtype=dtype,
device=device,
),
)
for _ in range(num_layers)
]
elif SYSTEM == "ipex" and device == torch.device("cpu"):
self.kv_cache = [
(
torch.empty(
(num_blocks, num_heads, BLOCK_SIZE, head_size),
dtype=dtype,
device=device,
),
torch.empty(
(num_blocks, num_heads, BLOCK_SIZE, head_size),
dtype=dtype,
device=device,
),
)
for _ in range(num_layers)
]
else:
self.kv_cache = [
(
torch.empty(
(num_blocks, num_heads, head_size // x, BLOCK_SIZE, x),
dtype=dtype,
device=device,
),
torch.empty(
(num_blocks, num_heads, head_size, BLOCK_SIZE),
dtype=dtype,
device=device,
),
)
for _ in range(num_layers)
]
def cuda_graph_warmup(self, bs: int, max_s: int, max_bt: int):
input_ids = torch.zeros(bs, dtype=torch.int64, device=self.device)
position_ids = torch.zeros(bs, dtype=torch.int32, device=self.device)
slots = torch.arange(bs, dtype=torch.int64, device=self.device)
input_lengths = torch.ones(bs, dtype=torch.int32, device=self.device) * max_s
block_tables = (
torch.arange(max_bt, dtype=torch.int32, device=self.device)
.repeat(bs)
.reshape((bs, max_bt))
)
self.cuda_graphs[bs] = {
"input_ids": input_ids,
"position_ids": position_ids,
"kv_cache": self.kv_cache,
"block_tables": block_tables,
"slots": slots,
"input_lengths": input_lengths,
}
input_lengths_ = Seqlen(input_lengths=input_lengths)
graph = torch.cuda.CUDAGraph()
self.cuda_graphs[bs]["graph"] = graph
if ATTENTION == "flashinfer":
from text_generation_server.layers.attention.flash_infer import (
create_decode_state_cuda_graphs,
)
block_tables_ptr = torch.zeros(
bs + 1, dtype=torch.int32, device=self.device
)
last_page_len = torch.ones(bs, dtype=torch.int32, device=self.device)
state = create_decode_state_cuda_graphs(
device=input_ids.device,
block_tables=block_tables.view(-1),
block_tables_ptr=block_tables_ptr,
last_page_len=last_page_len,
num_heads=self.num_heads,
num_kv_heads=self.num_kv_heads,
)
self.cuda_graphs[bs]["state"] = state
else:
state = None
torch.cuda.synchronize()
# Run once outside to warmup
with self._forward_context(
block_tables=block_tables,
cu_seqlen_prefill=None,
input_lengths=input_lengths,
state=state,
):
self.model.forward(
input_ids=input_ids,
position_ids=position_ids,
cu_seqlen_prefill=None,
kv_cache=self.kv_cache,
block_tables=block_tables,
slots=slots,
input_lengths=input_lengths_,
max_s=max_s,
prefill_cache_indices=None,
lm_head_indices=None,
)
torch.cuda.synchronize()
with torch.cuda.graph(graph, pool=MEM_POOL):
input_lengths = Seqlen(input_lengths=input_lengths)
logits, speculative_logits = self.model.forward(
input_ids=input_ids,
position_ids=position_ids,
cu_seqlen_prefill=None,
kv_cache=self.kv_cache,
block_tables=block_tables,
slots=slots,
input_lengths=input_lengths,
max_s=max_s,
prefill_cache_indices=None,
lm_head_indices=None,
)
self.cuda_graphs[bs]["logits"] = logits
self.cuda_graphs[bs]["speculative_logits"] = speculative_logits
torch.cuda.synchronize()
def warmup(self, batch: FlashCausalLMBatch):
# The warmup batch is the biggest batch we could ever receive
empty_cache()
try:
self.init_kv_cache(
batch.num_blocks,
self.num_layers,
self.num_kv_heads,
self.head_size,
self.dtype,
self.device,
)
max_bt = batch.max_blocks
max_s = max_bt * BLOCK_SIZE
if SYSTEM == "rocm" and os.environ.get("PYTORCH_TUNABLEOP_ENABLED", False):
torch.cuda.tunable.tuning_enable(False)
_, batch, _ = self.generate_token(batch)
except torch.cuda.OutOfMemoryError as e:
raise RuntimeError(
f"Not enough memory to handle {len(batch.input_ids)} prefill tokens. "
f"You need to decrease `--max-batch-prefill-tokens`"
) from e
synchronize(self.device)
# Inspired by the original implementation in [vllm](https://github.com/vllm-project/vllm)
# Calculate the number of blocks that can be allocated with the free memory
dtype_size = torch.tensor([], dtype=self.dtype).element_size()
cache_block_size = BLOCK_SIZE * self.num_kv_heads * self.head_size
total_cache_size = self.num_layers * cache_block_size * 2 * dtype_size
free_memory = get_free_memory(self.device, MEMORY_FRACTION)
batch_num_blocks = batch.num_blocks if batch is not None else 0
num_blocks = (
# Leave 5% for some wiggle room
int((free_memory * 0.95) // total_cache_size)
# Add batch.num_blocks as we allocated it above, so it is included in the peak memory.
+ batch_num_blocks
)
del batch
self.init_kv_cache(
num_blocks,
self.num_layers,
self.num_kv_heads,
self.head_size,
self.dtype,
self.device,
)
if SYSTEM == "rocm":
if (
os.environ.get("PYTORCH_TUNABLEOP_ENABLED") is None
or os.environ.get("PYTORCH_TUNABLEOP_ENABLED") == "1"
):
torch.cuda.tunable.enable()
if os.environ.get("PYTORCH_TUNABLEOP_TUNING") != "0":
torch.cuda.tunable.tuning_enable(True)
if os.environ.get("PYTORCH_TUNABLEOP_SEQLENS") is not None:
tuning_sequences = [
int(val)
for val in os.environ["PYTORCH_TUNABLEOP_SEQLENS"].split(",")
]
elif CUDA_GRAPHS is not None:
tuning_sequences = CUDA_GRAPHS
else:
# For seqlen = 1, we dispatch to LLMM1 kernel.
tuning_sequences = [2, 3, 4, 5, 6, 7]
tunableop_filepath = os.path.join(
HUGGINGFACE_HUB_CACHE,
f"tunableop_{self.model_id.replace('/', '-')}_tp{self.world_size}_rank{self.rank}.csv",
)
log_master(
logger.info,
f"PyTorch TunableOp (https://github.com/fxmarty/pytorch/tree/2.3-patched/aten/src/ATen/cuda/tunable) is enabled. The warmup may take several minutes, picking the ROCm optimal matrix multiplication kernel for the target lengths {', '.join([str(seqlen) for seqlen in tuning_sequences])}, with typical 5-8% latency improvement for small sequence lengths. The picked GEMMs are saved in the file {tunableop_filepath}. To disable TunableOp, please launch TGI with `PYTORCH_TUNABLEOP_ENABLED=0`.",
)
if os.path.isfile(tunableop_filepath):
log_master(
logger.info,
f"The file {tunableop_filepath} already exists and will be reused.",
)
torch.cuda.tunable.read_file(tunableop_filepath)
os.makedirs(HUGGINGFACE_HUB_CACHE, exist_ok=True)
for seqlen in tuning_sequences:
log_master(logger.info, f"Warming up TunableOp for seqlen={seqlen}")
self.tunableop_warmup(seqlen)
torch.cuda.tunable.write_file(tunableop_filepath)
torch.cuda.tunable.tuning_enable(False)
else:
log_master(
logger.info,
"PyTorch ROCm TunableOp (https://github.com/pytorch/pytorch/tree/main/aten/src/ATen/cuda/tunable) is disabled. TunableOp brings an additional 5-8% latency improvement for small sequence lengths but requires a warmup. If necessary, please use the environment variable PYTORCH_TUNABLEOP_ENABLED=1 to enable TunableOp.",
)
if CUDA_GRAPHS:
try:
log_master(
logger.info, f"Cuda Graphs are enabled for sizes {CUDA_GRAPHS}"
)
# Warmup cuda graphs
for bs in CUDA_GRAPHS:
if self.speculate is None or self.speculate + 1 <= bs:
self.cuda_graph_warmup(bs, max_s, max_bt)
except torch.cuda.OutOfMemoryError:
logger.exception("Decode cuda graph warmup failed")
else:
log_master(
logger.info, f"Cuda Graphs are disabled (CUDA_GRAPHS={CUDA_GRAPHS})."
)
return int(num_blocks * BLOCK_SIZE)
def tunableop_warmup(self, seqlen: int):
input_ids = torch.zeros(seqlen, dtype=torch.int64, device=self.device)
position_ids = torch.zeros(seqlen, dtype=torch.int32, device=self.device)
slots = torch.arange(seqlen, dtype=torch.int64, device=self.device)
# Dummy value, some models (starcoder2) don't accept `None`.
input_lengths = torch.ones(seqlen, dtype=torch.int32, device=self.device)
input_lengths = Seqlen(input_lengths=input_lengths)
# We pass a `cu_seqlen_prefill` in order not to have to deal with paged attention cache allocation/deallocation.
self.model.forward(
input_ids=input_ids,
position_ids=position_ids,
cu_seqlen_prefill=torch.tensor(
[0, seqlen], device=self.device, dtype=torch.int32
),
kv_cache=self.kv_cache,
block_tables=None,
input_lengths=input_lengths,
slots=slots,
max_s=seqlen,
lm_head_indices=None,
prefill_cache_indices=None,
)
def forward(
self, batch: FlashCausalLMBatch, adapter_data: AdapterBatchData
) -> Tuple[torch.Tensor, Optional[torch.Tensor]]:
# Model Forward
if batch.speculative_ids is not None:
input_ids = batch.input_ids
position_ids = batch.position_ids
cu_seqlen_prefill = batch.cu_seqlen_prefill
kv_cache = self.kv_cache
block_tables = batch.block_tables_tensor
slots = batch.slots[batch.slot_indices]
input_lengths = batch.input_lengths_tensor
max_s = batch.max_seqlen
lm_head_indices = batch.prefill_head_indices
speculative_ids = batch.speculative_ids
B, speculative_length = speculative_ids.shape
new_length = speculative_length + 1
new_input_ids = torch.cat(
[input_ids.unsqueeze(-1), speculative_ids], dim=1
).reshape(-1)
arange = torch.arange(new_length, device=position_ids.device).unsqueeze(0)
arange_int = arange.to(dtype=torch.int32)
new_position_ids = (
position_ids.unsqueeze(-1).expand(B, new_length) + arange
).view(-1)
slots = (slots.unsqueeze(-1).expand(B, new_length) + arange_int).view(-1)
input_lengths = (
input_lengths.unsqueeze(-1).expand(B, new_length) + arange_int
).view(-1)
# Add Copy the block tables for all members
block_tables = (
block_tables.unsqueeze(1)
.expand(B, new_length, -1)
.reshape(B * new_length, -1)
.contiguous()
)
max_s = max_s + speculative_length
input_ids = new_input_ids
position_ids = new_position_ids
else:
input_ids = batch.input_ids
position_ids = batch.position_ids
cu_seqlen_prefill = batch.cu_seqlen_prefill
kv_cache = self.kv_cache
block_tables = batch.block_tables_tensor
slots = batch.slots[batch.slot_indices]
input_lengths = batch.input_lengths_tensor
max_s = batch.max_seqlen
lm_head_indices = batch.prefill_head_indices
if cu_seqlen_prefill is None and self.max_past() is not None:
# In decode, not prefill, we're actually overwriting the KV-cache
# in a circular buffer mode.
# This makes sure the max_s for the decode pass is correct.
max_s = min(self.max_past(), max_s)
bs = input_ids.shape[0]
sorted_padded_bs = sorted([k for k in self.cuda_graphs.keys() if k >= bs])
if sorted_padded_bs:
# Get associated cuda graph
cuda_graph = self.cuda_graphs[sorted_padded_bs[0]]
else:
cuda_graph = None
if cu_seqlen_prefill is not None or cuda_graph is None:
with self._forward_context(
block_tables=block_tables,
cu_seqlen_prefill=cu_seqlen_prefill,
input_lengths=input_lengths,
):
input_lengths = Seqlen(input_lengths=input_lengths)
logits, speculative_logits = self.model.forward(
input_ids=input_ids,
position_ids=position_ids,
cu_seqlen_prefill=cu_seqlen_prefill,
kv_cache=kv_cache,
block_tables=block_tables,
slots=slots,
input_lengths=input_lengths,
max_s=max_s,
prefill_cache_indices=batch.prefill_cache_indices,
lm_head_indices=lm_head_indices,
adapter_data=adapter_data,
)
if batch.prefill_cache_indices is not None:
batch.prefill_cache_indices = None
return logits, speculative_logits
# Copy inputs to the static inputs of the cuda graph
# Static inputs are potentially padded
cuda_graph["input_ids"][: input_ids.shape[0]] = input_ids
cuda_graph["position_ids"][: position_ids.shape[0]] = position_ids
cuda_graph["block_tables"][
: block_tables.shape[0], : block_tables.shape[1]
] = block_tables
cuda_graph["slots"].fill_(-1)
cuda_graph["slots"][: slots.shape[0]] = slots
cuda_graph["input_lengths"].zero_()
cuda_graph["input_lengths"][: input_lengths.shape[0]] = input_lengths
state = cuda_graph.get("state")
with self._forward_context(
block_tables=block_tables,
cu_seqlen_prefill=None,
input_lengths=input_lengths,
state=state,
):
# Replay the graph
cuda_graph["graph"].replay()
# Slice output to the correct shape
speculative_logits = (
cuda_graph["speculative_logits"][:bs]
if cuda_graph["speculative_logits"] is not None
else None
)
logits = cuda_graph["logits"][:bs]
return logits, speculative_logits
@tracer.start_as_current_span("generate_token")
def generate_token(
self, batch: FlashCausalLMBatch
) -> Tuple[List[Generation], Optional[FlashCausalLMBatch], Tuple[int, int]]:
start = time.time_ns()
prefill = batch.cu_seqlen_prefill is not None
prefill_logprobs = batch.prefill_next_token_indices is not None
# Update adapter indices for speculative tokens (if present)
adapter_meta = batch.adapter_meta
if batch.speculative_ids is not None:
B, speculative_length = batch.speculative_ids.shape
new_length = speculative_length + 1
adapter_indices = (
adapter_meta.adapter_indices.unsqueeze(-1)
.expand(B, new_length)
.reshape(-1)
)
adapter_segments = adapter_meta.adapter_segments * new_length
adapter_meta = AdapterBatchMetadata(
adapter_indices=adapter_indices,
adapter_set=adapter_meta.adapter_set,
adapter_segments=adapter_segments,
segment_indices=adapter_meta.segment_indices,
)
# Assign pointers to adapter weights
# TODO(travis): don't update this if indices haven't changed
adapter_data = AdapterBatchData.from_meta(
adapter_meta,
self.layer_to_adapter_weights,
prefill,
batch.prefill_head_indices,
)
out, speculative_logits = self.forward(batch, adapter_data)
if prefill:
next_token_logits = (
out[batch.prefill_next_token_indices] if prefill_logprobs else out
)
if speculative_logits is not None:
speculative_logits = (
speculative_logits[batch.prefill_next_token_indices]
if prefill_logprobs
else speculative_logits
)
next_adapter_indices = batch.adapter_meta.adapter_indices.new_empty(
len(batch)
)
else:
next_token_logits = out
next_adapter_indices = batch.adapter_meta.adapter_indices
speculate = get_speculate()
(
next_input_ids,
next_token_logprobs,
logprobs,
accepted_ids,
speculative_ids,
) = batch.next_token_chooser(
batch.all_input_ids_tensor[:, : batch.max_seqlen],
next_token_logits,
speculate,
batch.speculative_ids,
speculative_logits,
)
batch_top_token_ids, batch_top_token_logprobs = batch_top_tokens(
batch.top_n_tokens, batch.top_n_tokens_tensor, logprobs, accepted_ids
)
if prefill:
if len(batch) > 1 and prefill_logprobs:
# We create the prefill_tokens_indices tensor that will be used to gather prefill logprobs
# When batch == 1, we will just use the batch.input_ids values directly
prefill_tokens_indices = batch.input_ids.new_zeros(len(out))
next_position_ids = batch.position_ids.new_empty(len(batch))
batch.slot_indices = batch.slot_indices[batch.cu_seqlen_prefill[1:] - 1]
# We do not need cu_seqlen_prefill anymore
batch.cu_seqlen_prefill = None
else:
prefill_logprobs = None
next_position_ids = batch.position_ids
# Cumulative length
cumulative_length = 0
# Results
generations: List[Generation] = []
stopped = True
# Zipped iterator
iterator = zip(batch.input_lengths, batch.all_input_ids, accepted_ids)
# We do two for loops as the first one can run completely asynchronously from the GPU while for the second
# one, we need to first do a GPU <-> CPU sync
# It is faster if we delay this sync for the maximum amount of time
# For each member of the batch
index = 0
for i, (input_length, all_input_ids, n_accepted_ids) in enumerate(iterator):
# Indexing metadata
start_index = cumulative_length
end_index = cumulative_length + input_length
if prefill:
# Indexing metadata
out_start_index = batch.prefill_cu_outlens[i]
out_end_index = batch.prefill_cu_outlens[i + 1]
out_length = out_end_index - out_start_index
# Initialize position_ids
# In decode, we do not need this as we can just increment position ids
next_position_ids[i] = batch.position_ids[end_index - 1]
# Initialize adapter indices
# In decode, we only have one token per row in the batch, so grab last index
next_adapter_indices[i] = batch.adapter_meta.adapter_indices[
end_index - 1
]
# Used to gather prefill logprobs
# Copy batch.input_ids to prefill_token_indices
if prefill_logprobs:
if len(batch) > 1:
prefill_tokens_indices[out_start_index : out_end_index - 1] = (
batch.input_ids[start_index + 1 : start_index + out_length]
)
else:
# Set prefill_tokens_indices to the correct slice
prefill_tokens_indices = batch.input_ids[
start_index + 1 : start_index + out_length
]
for j in range(n_accepted_ids):
batch.all_input_ids_tensor[i, input_length + j] = next_input_ids[index]
index += 1
cumulative_length += input_length
# Update values
batch.input_ids = next_input_ids[accepted_ids.cumsum(dim=-1) - 1]
batch.speculative_ids = speculative_ids
batch.position_ids = next_position_ids + accepted_ids
batch.input_lengths_tensor += accepted_ids
batch.slot_indices += accepted_ids
batch.adapter_meta.adapter_indices = next_adapter_indices
if prefill:
# adjust segment lengths to account for all request lengths being 1 during decoding
adapter_segments, _ = find_segments(batch.adapter_meta.adapter_indices)
batch.adapter_meta.adapter_segments = torch.tensor(
adapter_segments,
dtype=torch.int32,
device=batch.adapter_meta.adapter_segments.device,
)
if prefill and prefill_logprobs:
# Get prefill logprobs
prefill_logprobs_tensor = torch.log_softmax(out, -1)
prefill_logprobs = torch.gather(
prefill_logprobs_tensor, 1, prefill_tokens_indices.view(-1, 1)
)
# GPU <-> CPU sync
prefill_logprobs = prefill_logprobs.view(-1).tolist()
# GPU <-> CPU sync
next_token_logprobs = next_token_logprobs.tolist()
next_token_ids = next_input_ids.tolist()
accepted_ids = accepted_ids.tolist()
start_decode = time.time_ns()
# Zipped iterator
iterator = zip(
batch.requests,
batch.input_lengths,
batch.prefix_offsets,
batch.read_offsets,
batch.stopping_criterias,
batch.all_input_ids,
batch.next_token_chooser.do_sample,
batch.next_token_chooser.seeds,
batch.top_n_tokens,
accepted_ids,
batch_top_token_ids,
batch_top_token_logprobs,
)
# For each member of the batch
index = 0
for i, (
request,
input_length,
prefix_offset,
read_offset,
stopping_criteria,
all_input_ids,
do_sample,
seed,
top_n_tokens,
n_accepted_ids,
top_token_ids,
top_token_logprobs,
) in enumerate(iterator):
# Append next token to all tokens
next_token_texts = []
left = 0
if n_accepted_ids > 1:
log_master(logger.debug, f"Speculated ids {n_accepted_ids - 1}")
current_stopped = False
for j in range(index, index + n_accepted_ids):
# Generated token
next_token_id = next_token_ids[j]
all_input_ids.append(next_token_id)
next_token_text, prefix_offset, read_offset = self.decode_token(
all_input_ids,
prefix_offset,
read_offset,
)
next_token_texts.append(next_token_text)
stop, reason = stopping_criteria(
next_token_id,
next_token_text,
)
if stop:
left = index + n_accepted_ids - j - 1
current_stopped = True
break
else:
current_stopped = False
stopped = stopped and current_stopped
_next_token_ids = next_token_ids[index : index + n_accepted_ids - left]
_next_token_logprobs = next_token_logprobs[
index : index + n_accepted_ids - left
]
index += n_accepted_ids
# Shard generations
# All generations will be appended in the rust sharded client
if i % self.world_size == self.rank:
if stop:
# Decode generated tokens
output_text, _, _ = self.decode_token(
all_input_ids,
prefix_offset=len(all_input_ids)
- stopping_criteria.current_tokens
- 1,
read_offset=len(all_input_ids)
- stopping_criteria.current_tokens,
skip_special_tokens=True,
)
generated_text = GeneratedText(
output_text,
stopping_criteria.current_tokens,
reason,
seed if do_sample else None,
)
else:
generated_text = None
# Prefill
if prefill and request.prefill_logprobs:
out_start_index = batch.prefill_cu_outlens[i]
out_end_index = batch.prefill_cu_outlens[i + 1]
# Remove generated token to only have prefill and add nan for first prompt token
request_prefill_logprobs = [float("nan")] + prefill_logprobs[
out_start_index : out_end_index - 1
]
prefill_token_ids = all_input_ids[:-1]
prefill_texts = self.tokenizer.batch_decode(
prefill_token_ids,
clean_up_tokenization_spaces=False,
skip_special_tokens=False,
)
prefill_tokens = Tokens(
prefill_token_ids,
request_prefill_logprobs,
prefill_texts,
is_special=[],
)
else:
prefill_tokens = None
if top_n_tokens > 0:
all_top_tokens = []
for top_token_ids, top_token_logprobs in zip(
top_token_ids, top_token_logprobs
):
toptoken_texts = self.tokenizer.batch_decode(
top_token_ids,
clean_up_tokenization_spaces=False,
skip_special_tokens=False,
)
special_toptokens = [
token_id in self.all_special_ids
for token_id in top_token_ids
]
top_tokens = Tokens(
top_token_ids,
top_token_logprobs,
toptoken_texts,
special_toptokens,
)
all_top_tokens.append(top_tokens)
top_tokens = all_top_tokens
else:
top_tokens = None
generation = Generation(
request.id,
prefill_tokens,
Tokens(
_next_token_ids,
_next_token_logprobs,
next_token_texts,
[nid in self.all_special_ids for nid in _next_token_ids],
),
generated_text,
top_tokens,
)
generations.append(generation)
# accept each new token for this specific request since we may
# have more than one new token per request with speculative decoding
for next_token_id in _next_token_ids:
batch.next_token_chooser = (
batch.next_token_chooser.advance_grammar_single(i, next_token_id)
)
# Update values
batch.input_lengths[i] = input_length + n_accepted_ids
if batch.input_lengths[i] > batch.max_seqlen:
batch.max_seqlen = batch.input_lengths[i]
batch.prefix_offsets[i] = prefix_offset
batch.read_offsets[i] = read_offset
batch.all_input_ids[i] = all_input_ids
if stopped:
# No need to return a batch if we know that all requests stopped
forward_ns = start_decode - start
decode_ns = time.time_ns() - start_decode
return generations, None, (forward_ns, decode_ns)
batch.prefill_cu_outlens = None
batch.prefill_head_indices = None
batch.prefill_next_token_indices = None
forward_ns = start_decode - start
decode_ns = time.time_ns() - start_decode
return generations, batch, (forward_ns, decode_ns)
def _forward_context(
self,
*,
block_tables: torch.Tensor,
cu_seqlen_prefill: Optional[torch.Tensor],
input_lengths: torch.Tensor,
state: Optional[Any] = None,
) -> ContextManager:
if ATTENTION != "flashinfer":
return nullcontext()
from text_generation_server.layers.attention.flash_infer import (
use_decode_state,
use_prefill_state,
)
if cu_seqlen_prefill is not None:
return use_prefill_state(
state=state if state is not None else self.prefill_state,
cu_seqlens=cu_seqlen_prefill,
num_heads=self.num_heads,
num_kv_heads=self.num_kv_heads,
head_size=self.head_size,
)
else:
assert input_lengths is not None
return use_decode_state(
state=state if state is not None else self.decode_state,
input_lengths=input_lengths,
block_tables=block_tables.view(-1),
num_heads=self.num_heads,
num_kv_heads=self.num_kv_heads,
head_size=self.head_size,
page_size=BLOCK_SIZE,
)