Files
project_6/vllm/beam_search.py
dylanyunlon ef6abf3dc7 [DEPLOY] Complete submission: baseline + all optimizations
Adds ALL files needed for Dockerfile build:
  - qwen3_6_scripts/ (baseline patches + our optimizations)
  - vllm/ (full vllm package)
  - paged_attention_v2_pytorch.py (V2 with single-bmm optimization)
  - Dockerfile + computility-run.yaml

Our optimizations vs baseline:
  1. paged_attn.py: pre-gathered context KV (eliminates 194 gather calls),
     Triton try/fallback, V2 heuristic, threshold 32K→64K
  2. paged_attention_v2_pytorch.py: fills NotImplementedError,
     single-bmm Phase 1 (195 launches → 3)
  3. patch_enable_triton.py: HAS_TRITON=True with safety fallback
  4. patch_triton_tuning.py: BLOCK=64, NUM_WARPS=4 for BI-V100
  5. computility-run.yaml: gpu-memory-utilization 0.9→0.95,
     max-num-batched-tokens 8192→16384

This repo can now be submitted to dev.modelhub.org.cn as-is.
2026-07-30 16:06:20 +00:00

62 lines
1.7 KiB
Python

from dataclasses import dataclass
from typing import List, Optional
@dataclass
class BeamSearchSequence:
"""A sequence for beam search.
It keeps track of the tokens and the log probability of the sequence.
The text field is optional and will only be filled when the sequence is
about to be returned to the user.
"""
# The tokens includes the prompt.
tokens: List[int]
cum_logprob: float = 0.0
text: Optional[str] = None
@dataclass
class BeamSearchOutput:
"""The output of beam search.
It contains the list of the best beam search sequences.
The length of the list is equal to the beam width.
"""
sequences: List[BeamSearchSequence]
class BeamSearchInstance:
def __init__(self, prompt_tokens: List[int]):
self.beams: List[BeamSearchSequence] = [
BeamSearchSequence(tokens=prompt_tokens)
]
self.completed: List[BeamSearchSequence] = []
def get_beam_search_score(
tokens: List[int],
cumulative_logprob: float,
eos_token_id: int,
length_penalty: float = 1.0,
) -> float:
"""Calculate the beam search score with length penalty.
Adapted from
https://github.com/huggingface/transformers/blob/ccb92be23def445f2afdea94c31286f84b89eb5b/src/transformers/generation/beam_search.py#L938
"""
seq_len = len(tokens)
if tokens[-1] == eos_token_id:
seq_len -= 1
return cumulative_logprob / (seq_len**length_penalty)
def create_sort_beams_key_function(eos_token_id: int, length_penalty: float):
def sort_beams_key(x: BeamSearchSequence) -> float:
return get_beam_search_score(x.tokens, x.cum_logprob, eos_token_id,
length_penalty)
return sort_beams_key