[Bugfix] fix beam search input errors and latency benchmark script (#11875)

Signed-off-by: Ye Qi <yeq@meta.com>
Co-authored-by: yeq <yeq@devgpu004.lla3.facebook.com>

benchmarks/benchmark_latency.py

@@ -13,6 +13,7 @@ from tqdm import tqdm
 from vllm import LLM, SamplingParams
 from vllm.engine.arg_utils import EngineArgs
 from vllm.inputs import PromptType
+from vllm.sampling_params import BeamSearchParams
 from vllm.utils import FlexibleArgumentParser
 
 
@@ -40,6 +41,20 @@ def main(args: argparse.Namespace):
         "prompt_token_ids": batch
     } for batch in dummy_prompt_token_ids.tolist()]
 
+    def llm_generate():
+        if not args.use_beam_search:
+            llm.generate(dummy_prompts,
+                         sampling_params=sampling_params,
+                         use_tqdm=False)
+        else:
+            llm.beam_search(
+                dummy_prompts,
+                BeamSearchParams(
+                    beam_width=args.n,
+                    max_tokens=args.output_len,
+                    ignore_eos=True,
+                ))
+
     def run_to_completion(profile_dir: Optional[str] = None):
         if profile_dir:
             with torch.profiler.profile(
@@ -49,15 +64,11 @@ def main(args: argparse.Namespace):
                     ],
                     on_trace_ready=torch.profiler.tensorboard_trace_handler(
                         str(profile_dir))) as p:
-                llm.generate(dummy_prompts,
-                             sampling_params=sampling_params,
-                             use_tqdm=False)
+                llm_generate()
             print(p.key_averages().table(sort_by="self_cuda_time_total"))
         else:
             start_time = time.perf_counter()
-            llm.generate(dummy_prompts,
-                         sampling_params=sampling_params,
-                         use_tqdm=False)
+            llm_generate()
             end_time = time.perf_counter()
             latency = end_time - start_time
             return latency

vllm/entrypoints/llm.py

@@ -21,7 +21,7 @@ from vllm.entrypoints.chat_utils import (ChatCompletionMessageParam,
                                          parse_chat_messages,
                                          resolve_chat_template_content_format)
 from vllm.inputs import PromptType, SingletonPrompt, TextPrompt, TokensPrompt
-from vllm.inputs.parse import parse_and_batch_prompt
+from vllm.inputs.parse import is_token_prompt, parse_and_batch_prompt
 from vllm.logger import init_logger
 from vllm.lora.request import LoRARequest
 from vllm.model_executor.guided_decoding.guided_fields import (
@@ -457,7 +457,7 @@ class LLM:
 
     def beam_search(
         self,
-        prompts: List[Union[str, List[int]]],
+        prompts: List[Union[TokensPrompt, TextPrompt]],
         params: BeamSearchParams,
     ) -> List[BeamSearchOutput]:
         """
@@ -493,8 +493,10 @@ class LLM:
         instances: List[BeamSearchInstance] = []
 
         for prompt in prompts:
-            prompt_tokens = prompt if isinstance(
-                prompt, list) else tokenizer.encode(prompt)
+            if is_token_prompt(prompt):
+                prompt_tokens = prompt["prompt_token_ids"]
+            else:
+                prompt_tokens = tokenizer.encode(prompt["prompt"])
             instances.append(BeamSearchInstance(prompt_tokens))
 
         for _ in range(max_tokens):