[V0 Deprecation] Remove LLMEngine (#25033)

Signed-off-by: Woosuk Kwon <woosuk@thinkingmachines.ai>
Signed-off-by: Woosuk Kwon <woosuk.kwon@berkeley.edu>

tests/plugins_tests/test_scheduler_plugins.py

@@ -3,47 +3,18 @@
 
 import pytest
 
-from vllm.core.scheduler import Scheduler
 from vllm.engine.arg_utils import EngineArgs
-from vllm.engine.llm_engine import LLMEngine
 from vllm.sampling_params import SamplingParams
-from vllm.v1.core.sched.scheduler import Scheduler as V1Scheduler
-from vllm.v1.engine.llm_engine import LLMEngine as V1LLMEngine
+from vllm.v1.core.sched.scheduler import Scheduler
+from vllm.v1.engine.llm_engine import LLMEngine
 
 
-class DummyV0Scheduler(Scheduler):
-
-    def schedule(self):
-        raise Exception("Exception raised by DummyV0Scheduler")
-
-
-class DummyV1Scheduler(V1Scheduler):
+class DummyV1Scheduler(Scheduler):
 
     def schedule(self):
         raise Exception("Exception raised by DummyV1Scheduler")
 
 
-def test_scheduler_plugins_v0(monkeypatch: pytest.MonkeyPatch):
-    with monkeypatch.context() as m:
-        m.setenv("VLLM_USE_V1", "0")
-        with pytest.raises(Exception) as exception_info:
-
-            engine_args = EngineArgs(
-                model="facebook/opt-125m",
-                enforce_eager=True,  # reduce test time
-                scheduler_cls=DummyV0Scheduler,
-            )
-
-            engine = LLMEngine.from_engine_args(engine_args=engine_args)
-
-            sampling_params = SamplingParams(max_tokens=1)
-            engine.add_request("0", "foo", sampling_params)
-            engine.step()
-
-        assert str(
-            exception_info.value) == "Exception raised by DummyV0Scheduler"
-
-
 def test_scheduler_plugins_v1(monkeypatch: pytest.MonkeyPatch):
     with monkeypatch.context() as m:
         m.setenv("VLLM_USE_V1", "1")
@@ -59,7 +30,7 @@ def test_scheduler_plugins_v1(monkeypatch: pytest.MonkeyPatch):
                 scheduler_cls=DummyV1Scheduler,
             )
 
-            engine = V1LLMEngine.from_engine_args(engine_args=engine_args)
+            engine = LLMEngine.from_engine_args(engine_args=engine_args)
 
             sampling_params = SamplingParams(max_tokens=1)
             engine.add_request("0", "foo", sampling_params)

tests/samplers/test_beam_search.py

@@ -10,13 +10,6 @@ from transformers import AutoModelForSeq2SeqLM
 
 from vllm.assets.audio import AudioAsset
 
-
-@pytest.fixture(autouse=True)
-def v1(run_with_both_engines):
-    """We can run both engines for this test."""
-    pass
-
-
 # FIXME(zhuohan): The test can not pass if we:
 #   1. Increase max_tokens to 256.
 #   2. Increase beam_width to 8.

tests/samplers/test_ignore_eos.py

@@ -9,13 +9,6 @@ import pytest
 
 from vllm import SamplingParams
 
-
-@pytest.fixture(autouse=True)
-def v1(run_with_both_engines):
-    """We can run both engines for this test."""
-    pass
-
-
 # We also test with llama because it has generation_config to specify EOS
 # (past regression).
 MODELS = ["distilbert/distilgpt2", "meta-llama/Llama-3.2-1B"]

tests/samplers/test_ranks.py

@@ -8,12 +8,6 @@ from vllm import SamplingParams
 MODELS = ["distilbert/distilgpt2"]
 
 
-@pytest.fixture(autouse=True)
-def v1(run_with_both_engines):
-    """We can run both engines for this test."""
-    pass
-
-
 @pytest.mark.parametrize("model", MODELS)
 @pytest.mark.parametrize("dtype", ["half"])
 def test_ranks(

tests/tokenization/test_detokenize.py

@@ -352,58 +352,3 @@ def test_decode_prompt_logprobs(complete_sequence: str,
         logprobs[token_id + 1].decoded_token
         for token_id, logprobs in zip(token_ids[1:], decoded_prompt_logprobs)
     ])
-
-
-@pytest.mark.parametrize("model", ["facebook/opt-125m"])
-@pytest.mark.parametrize("chunked_prefill_token_size", [1, 4, 7, 16, -1])
-def test_decode_prompt_logprobs_chunked_prefill(
-    vllm_runner,
-    model,
-    chunked_prefill_token_size: int,
-    example_prompts,
-    monkeypatch,
-):
-    # VLLM V1 does not use incremental detokenization for
-    # prompt logprobs, so this test strategy is irrelevant.
-    monkeypatch.setenv("VLLM_USE_V1", "0")
-
-    max_num_seqs = 256
-    enable_chunked_prefill = False
-    max_num_batched_tokens = None
-    if chunked_prefill_token_size != -1:
-        enable_chunked_prefill = True
-        max_num_seqs = min(chunked_prefill_token_size, max_num_seqs)
-        max_num_batched_tokens = chunked_prefill_token_size
-
-    with vllm_runner(model,
-                     dtype="half",
-                     max_logprobs=5,
-                     gpu_memory_utilization=0.5,
-                     enable_chunked_prefill=enable_chunked_prefill,
-                     max_num_batched_tokens=max_num_batched_tokens,
-                     max_num_seqs=max_num_seqs) as vllm_model:
-
-        vllm_sampling_params = SamplingParams(max_tokens=10,
-                                              logprobs=5,
-                                              prompt_logprobs=5,
-                                              temperature=0.0)
-        vllm_results = vllm_model.llm.generate(
-            example_prompts, sampling_params=vllm_sampling_params)
-
-        for idx, result in enumerate(vllm_results):
-            assert result.prompt_logprobs is not None
-            assert result.prompt_logprobs[0] is None
-
-            # Compared detokenized prompts ids to original prompt.
-            generated_string = ""
-            for (prompt_token,
-                 prompt_logprobs) in zip(result.prompt_token_ids[1:],
-                                         result.prompt_logprobs[1:]):
-                # prompt_logprobs is a dict of the token_id: logprob
-                # We select the token_id corresponding to the actual prompt
-                # Decoded token in the detokenized string corresponding to this
-                # prompt token.
-                generated_string += prompt_logprobs[prompt_token].decoded_token
-
-            assert generated_string == example_prompts[idx], (
-                "Detokenized prompt logprobs do not match original prompt")

vllm/engine/arg_utils.py

@@ -1508,14 +1508,6 @@ class EngineArgs:
                                recommend_to_remove=True)
             return False
 
-        if self.kv_cache_dtype != "auto":
-            supported = current_platform.is_kv_cache_dtype_supported(
-                self.kv_cache_dtype, model_config)
-            if not supported:
-                _raise_or_fallback(feature_name="--kv-cache-dtype",
-                                   recommend_to_remove=False)
-                return False
-
         # No Mamba or Encoder-Decoder so far.
         if not model_config.is_v1_compatible:
             _raise_or_fallback(feature_name=model_config.architectures,

vllm/entrypoints/llm.py

@@ -11,7 +11,6 @@ from pydantic import ValidationError
 from tqdm.auto import tqdm
 from typing_extensions import TypeVar
 
-import vllm.envs as envs
 from vllm.beam_search import (BeamSearchInstance, BeamSearchOutput,
                               BeamSearchSequence,
                               create_sort_beams_key_function)
@@ -19,7 +18,6 @@ from vllm.config import (CompilationConfig, ModelDType,
                          StructuredOutputsConfig, TokenizerMode, is_init_field)
 from vllm.engine.arg_utils import (ConvertOption, EngineArgs, HfOverrides,
                                    PoolerConfig, RunnerOption)
-from vllm.engine.llm_engine import LLMEngine
 from vllm.entrypoints.chat_utils import (ChatCompletionMessageParam,
                                          ChatTemplateContentFormatOption,
                                          apply_hf_chat_template,
@@ -54,6 +52,7 @@ from vllm.transformers_utils.tokenizer import (AnyTokenizer, MistralTokenizer,
                                                get_cached_tokenizer)
 from vllm.usage.usage_lib import UsageContext
 from vllm.utils import Counter, Device, as_iter, is_list_of
+from vllm.v1.engine.llm_engine import LLMEngine
 from vllm.v1.sample.logits_processor import LogitsProcessor
 
 if TYPE_CHECKING:
@@ -309,11 +308,7 @@ class LLM:
         self.request_counter = Counter()
         self.default_sampling_params: Union[dict[str, Any], None] = None
 
-        if envs.VLLM_USE_V1:
-            supported_tasks = self.llm_engine \
-                .get_supported_tasks()  # type: ignore
-        else:
-            supported_tasks = self.llm_engine.model_config.supported_tasks
+        supported_tasks = self.llm_engine.get_supported_tasks()  # type: ignore
 
         logger.info("Supported_tasks: %s", supported_tasks)
 
@@ -1473,8 +1468,6 @@ class LLM:
         Note:
             This method is only available with the V1 LLM engine.
         """
-        from vllm.v1.engine.llm_engine import LLMEngine as V1LLMEngine
-        assert isinstance(self.llm_engine, V1LLMEngine)
         return self.llm_engine.get_metrics()
 
     def _validate_and_add_requests(

vllm/model_executor/model_loader/tensorizer.py

@@ -672,17 +672,11 @@ def tensorize_vllm_model(engine_args: "EngineArgs",
         ) as stream:
             stream.write(encryption_params.key)
 
-    from vllm import LLMEngine
-    from vllm.v1.engine.llm_engine import LLMEngine as V1LLMEngine
+    assert envs.VLLM_USE_V1
 
-    if not envs.VLLM_USE_V1:
-        engine = LLMEngine.from_engine_args(engine_args)
-        engine.model_executor.collective_rpc(
-            "save_tensorized_model",
-            kwargs={"tensorizer_config": tensorizer_config.to_serializable()},
-        )
-    else:
-        engine = V1LLMEngine.from_vllm_config(engine_config)
+    from vllm.v1.engine.llm_engine import LLMEngine
+
+    engine = LLMEngine.from_vllm_config(engine_config)
     engine.collective_rpc(
         "save_tensorized_model",
         kwargs={"tensorizer_config": tensorizer_config.to_serializable()},