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685
tests/v1/sample/test_logprobs.py
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685
tests/v1/sample/test_logprobs.py
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# SPDX-License-Identifier: Apache-2.0
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# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
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import itertools
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import math
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from collections.abc import Generator
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from typing import get_args
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import pytest
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import torch
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from tests.utils import large_gpu_mark
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from tests.v1.sample.utils import (
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BatchLogprobsComposition,
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BatchLogprobsSpecType,
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assert_incr_detok_str_matches_non_incr_detok_str,
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compute_correct_cumulative_logprob,
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get_test_batch,
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)
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from vllm import SamplingParams
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from vllm.config.model import LogprobsMode
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from vllm.distributed import cleanup_dist_env_and_memory
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from ...conftest import HfRunner, VllmRunner
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MODEL = "meta-llama/Llama-3.2-1B-Instruct"
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DTYPE = "half"
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NONE = BatchLogprobsComposition.NONE
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SAMPLE = BatchLogprobsComposition.SAMPLE
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PROMPT = BatchLogprobsComposition.PROMPT
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SAMPLE_PROMPT = BatchLogprobsComposition.SAMPLE_PROMPT
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@pytest.fixture(
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scope="module",
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# Parameterize APC
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params=[False, True],
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)
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def vllm_model(vllm_runner, request) -> Generator[VllmRunner, None, None]:
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with vllm_runner(
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MODEL,
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dtype=DTYPE,
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max_logprobs=7,
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# Very small number of batched tokens to ensure
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# that we test chunking.
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max_num_batched_tokens=16,
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max_num_seqs=16,
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max_model_len=128,
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enable_chunked_prefill=True,
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enforce_eager=True,
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# TODO: enable this once we support it for
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# prompt logprobs.
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enable_prefix_caching=request.param,
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gpu_memory_utilization=0.4, # up to 2 alive concurrently
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) as vllm_model:
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yield vllm_model
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@pytest.fixture(scope="module")
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def hf_model(hf_runner) -> Generator[HfRunner, None, None]:
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with hf_runner(MODEL, dtype=DTYPE) as hf_model:
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yield hf_model
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def _repeat_logprob_config(
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test_prompts,
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logprob_prompt_logprob_list: BatchLogprobsSpecType,
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) -> BatchLogprobsSpecType:
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"""Ensure each test prompt has a logprob config.
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A logprob config specifies the optional (i.e.
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may-be-`None`) number of sample logprobs and
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the optional number of prompt logprobs.
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If more test prompts than logprob configs are
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provided, the provided logprob configs are
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tiled to match the number of test prompts.
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If fewer test prompts than logprob configs
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are provided, the list of logprob configs
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is truncated to match the number of test
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prompts.
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Otherwise, the list of logprob configs
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is returned as-is.
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Args:
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test_prompts: list of prompts under test
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logprob_prompt_logprob_list: list of
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(optional num sample logprob,
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optional num prompt logprob)
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tuples
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Returns:
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list of
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(optional num sample logprob,optional num prompt logprob)
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tuples which is either identical to
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`logprob_prompt_logprob_list`, or else repeats
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`logprob_prompt_logprob_list` enough times to match the
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number of `test_prompts`, or else is truncated to match
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the number of `test_prompts`
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"""
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num_test_prompts = len(test_prompts)
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# Make sure there is a logprobs configuration for each test prompt
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logprob_prompt_logprob_list = list(
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itertools.islice(itertools.cycle(logprob_prompt_logprob_list), num_test_prompts)
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)
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# Now the number of prompts should match the number of sample params combos
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assert num_test_prompts == len(logprob_prompt_logprob_list)
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return logprob_prompt_logprob_list
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def _run_and_validate(
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vllm_model: VllmRunner,
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test_prompts: list[str],
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vllm_sampling_params: SamplingParams,
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hf_logprobs: list[list[torch.Tensor]],
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hf_outputs: list[tuple[list[int], str]],
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logprob_prompt_logprob_list: BatchLogprobsSpecType,
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temperature: float,
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max_tokens: int,
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do_apc: bool,
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) -> None:
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vllm_results = vllm_model.llm.generate(
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test_prompts, sampling_params=vllm_sampling_params
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)
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for vllm_result, hf_logprob, hf_output, logprob_prompt_logprob in zip(
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vllm_results, hf_logprobs, hf_outputs, logprob_prompt_logprob_list
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):
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# Extract request-level (prompt)logprobs config
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num_top_logprobs, num_top_prompt_logprobs = logprob_prompt_logprob
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# Test whether sampled token output is consistent between vLLM and HF
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# vLLM prompt+completion should match HF output
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if temperature == 0.0:
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assert (
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vllm_result.prompt_token_ids + vllm_result.outputs[0].token_ids
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== hf_output[0]
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)
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else:
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# Sampled tokens won't match if not greedy
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assert (
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vllm_result.prompt_token_ids
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== hf_output[0][: len(vllm_result.prompt_token_ids)]
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)
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# Validate sample logprobs
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if num_top_logprobs is not None:
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assert num_top_logprobs is not None
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# Confirm that the structure of the sample logprobs in the result is
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# correct
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assert vllm_result.outputs[0].logprobs is not None
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assert len(vllm_result.outputs[0].logprobs) == max_tokens
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for logprobs, token_id in zip(
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vllm_result.outputs[0].logprobs, vllm_result.outputs[0].token_ids
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):
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assert logprobs is not None
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# Confirm that the output token appears among the logprobs
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assert token_id in logprobs
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token_in_topk = logprobs[token_id].rank <= num_top_logprobs
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# If the output token is not included in the top K
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# logprob, it can return 1 more data
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if token_in_topk and num_top_logprobs != 0:
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assert len(logprobs) == num_top_logprobs
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else:
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assert len(logprobs) == num_top_logprobs + 1
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if num_top_logprobs > 0:
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# We should have an entry for each of the topk ranks
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all_ranks = {lp.rank for lp in logprobs.values()}
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assert all(r in all_ranks for r in range(1, num_top_logprobs + 1))
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output_text = vllm_result.outputs[0].text
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output_string_from_most_likely_tokens_lst: list[str] = []
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for top_logprobs in vllm_result.outputs[0].logprobs:
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top_logprob = next(iter(top_logprobs.values()))
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output_string_from_most_likely_tokens_lst.append(
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top_logprob.decoded_token
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)
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output_string_from_most_likely_tokens = "".join(
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output_string_from_most_likely_tokens_lst
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)
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assert_incr_detok_str_matches_non_incr_detok_str(
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output_text,
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output_string_from_most_likely_tokens,
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"The output text from the top logprob for each token "
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"position should be the same as the output text in the "
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"result.",
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)
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# Compare vLLM sample logprobs to HF
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vllm_sample_logprobs = vllm_result.outputs[0].logprobs
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for i, top_logprobs in enumerate(vllm_sample_logprobs):
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for token_id, sample_logprob in top_logprobs.items():
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if temperature == 0.0 or i == 0:
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logprob = sample_logprob.logprob
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torch.testing.assert_close(
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logprob,
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hf_logprob[i][-1][token_id].item(),
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atol=1e-2,
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rtol=1e-2,
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)
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assert isinstance(sample_logprob.decoded_token, str), (
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"The token should be decoded by the time it is"
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" returned to the user."
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)
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# At this point we know the sample logprobs are correct for this
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# request. Validate that cumulative_logprob is actually the sum.
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# For each request, assert that the returned cumulative logprob
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# matches the correct value, which is computed below.
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torch.testing.assert_close(
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vllm_result.outputs[0].cumulative_logprob,
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compute_correct_cumulative_logprob(vllm_result.outputs[0]),
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atol=1e-6,
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rtol=1e-6,
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)
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else:
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# Logprobs disabled for this request; should be None
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assert vllm_result.outputs[0].logprobs is None
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# Validate prompt logprobs
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if num_top_prompt_logprobs is not None:
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# Confirm that structure of prompt logprobs in result is correct
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assert vllm_result.prompt_logprobs is not None
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# - The first prompt logprob is always None
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assert vllm_result.prompt_logprobs[0] is None
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# - Prompt logprobs are returned for all indices in
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# the prompt
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assert len(vllm_result.prompt_logprobs) == len(vllm_result.prompt_token_ids)
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for prompt_logprobs, prompt_token_id in zip(
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vllm_result.prompt_logprobs[1:], vllm_result.prompt_token_ids[1:]
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):
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assert prompt_logprobs is not None
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# Confirm that the prompt token appears among the logprobs
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assert prompt_token_id in prompt_logprobs
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token_in_topk = (
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prompt_logprobs[prompt_token_id].rank <= num_top_prompt_logprobs
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)
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# If the prompt token is not included in the top K
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# logprob, it can return 1 more data
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if token_in_topk and num_top_prompt_logprobs != 0:
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assert len(prompt_logprobs) == num_top_prompt_logprobs
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else:
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assert len(prompt_logprobs) == num_top_prompt_logprobs + 1
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if num_top_prompt_logprobs > 0:
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# We should have an entry for each of the topk ranks
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all_ranks = {lp.rank for lp in prompt_logprobs.values()}
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assert all(
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r in all_ranks for r in range(1, num_top_prompt_logprobs + 1)
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)
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# Compare prompt logprobs to HF
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# The first prompt logprob is always None, so we compare it from
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# 1:.
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vllm_prompt_logprobs = vllm_result.prompt_logprobs[1:]
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for i, vllm_prompt_logprob_dict in enumerate(vllm_prompt_logprobs):
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for token_id, logprob in vllm_prompt_logprob_dict.items():
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torch.testing.assert_close(
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logprob.logprob,
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hf_logprob[0][i][token_id].item(),
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atol=2e-2,
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rtol=2e-2,
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)
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else:
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assert vllm_result.prompt_logprobs is None
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@pytest.mark.parametrize(
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"batch_logprobs_composition", [NONE, SAMPLE, PROMPT, SAMPLE_PROMPT]
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)
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@pytest.mark.parametrize("temperature", [0.0, 2.0])
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def test_get_logprobs_and_prompt_logprobs(
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hf_model,
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vllm_model,
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batch_logprobs_composition: BatchLogprobsComposition,
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temperature: float,
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example_prompts: list[str],
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) -> None:
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"""Test V1 Engine logprobs & prompt logprobs
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Exercise a variety of combinations of `logprobs` and `prompt_logprobs`
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settings and validate that
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* The generated logprobs and prompt logprobs are consistent with the
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configuration settings, in terms of whether or not the logprobs
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(of either type) were requested and how many were requested
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* The generated logprobs are consistent with the generated tokens
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* The generated (prompt)logprobs are consistent with HuggingFace
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(prompt)logprobs, as a reference
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batch_logprobs_composition controls the logprobs configurations for
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requests in the batch under test.
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APC tests run two test iterations so that cache hits occur.
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To save time, only test one APC-enabled scenario
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(sample & prompt logprobs enabled, temperature>0.0).
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Args:
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hf_model: HuggingFace reference model fixture
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vllm_model: vLLM model fixture
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batch_logprobs_composition: logprobs configuration for test batch
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temperature: "temperature" sampling parameter
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example_prompts: example prompt fixture
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"""
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do_apc = vllm_model.llm.llm_engine.cache_config.enable_prefix_caching
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if do_apc and (temperature < 2.0 or batch_logprobs_composition != SAMPLE_PROMPT):
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# Skip some test-cases to save time.
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pytest.skip()
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test_prompts = example_prompts
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max_tokens = 5
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hf_outputs = hf_model.generate_greedy(
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test_prompts,
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max_tokens=max_tokens,
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)
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hf_logprobs = hf_model.generate_greedy_logprobs(
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test_prompts,
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max_tokens=max_tokens,
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)
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# Batch has mixed sample params
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# (different logprobs/prompt logprobs combos)
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logprob_prompt_logprob_list = get_test_batch(batch_logprobs_composition)
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# Ensure that each test prompt has a logprob config for testing
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logprob_prompt_logprob_list = _repeat_logprob_config(
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test_prompts, logprob_prompt_logprob_list
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)
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# Generate SamplingParams
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vllm_sampling_params = [
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SamplingParams(
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max_tokens=max_tokens,
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logprobs=num_lp,
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prompt_logprobs=num_plp,
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temperature=temperature,
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seed=1984,
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)
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for num_lp, num_plp in logprob_prompt_logprob_list
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]
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for _ in range(2 if do_apc else 1):
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_run_and_validate(
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vllm_model=vllm_model,
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test_prompts=test_prompts,
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vllm_sampling_params=vllm_sampling_params,
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hf_logprobs=hf_logprobs,
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hf_outputs=hf_outputs,
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logprob_prompt_logprob_list=logprob_prompt_logprob_list,
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temperature=temperature,
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max_tokens=max_tokens,
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do_apc=do_apc,
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)
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def test_max_logprobs():
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"""vLLM v1 engine should fail a request with `logprobs > max_logprobs`
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Should also fail for `prompt_logprobs > max_logprobs`
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APC should not matter as this test checks basic request validation.
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"""
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runner = VllmRunner(
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"facebook/opt-125m",
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max_logprobs=1,
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enable_prefix_caching=False,
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# 2 other llms alive during whole session
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gpu_memory_utilization=0.15,
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max_model_len=256,
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)
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vllm_sampling_params = SamplingParams(logprobs=1)
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# should pass
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runner.generate(["Hello world"], sampling_params=vllm_sampling_params)
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bad_sampling_params = SamplingParams(logprobs=2)
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with pytest.raises(ValueError):
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runner.generate(["Hello world"], sampling_params=bad_sampling_params)
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def test_none_logprobs(vllm_model, example_prompts):
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"""Engine should return `logprobs` and `prompt_logprobs` as `None`
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Args:
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vllm_model: vLLM model fixture
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example_prompts: list of example prompts (test fixture)
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"""
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max_tokens = 5
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sampling_params_logprobs_none = SamplingParams(
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max_tokens=max_tokens,
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logprobs=None,
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prompt_logprobs=None,
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temperature=0.0,
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)
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results_logprobs_none = vllm_model.llm.generate(
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example_prompts,
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sampling_params=sampling_params_logprobs_none,
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)
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for i in range(len(results_logprobs_none)):
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# Check sample logprobs are None
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assert results_logprobs_none[i].outputs[0].logprobs is None
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assert results_logprobs_none[i].outputs[0].cumulative_logprob is None
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# Check prompt logprobs are None
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assert results_logprobs_none[i].prompt_logprobs is None
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|
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def test_zero_logprobs(vllm_model, example_prompts):
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"""Engine should return sampled token and prompt token logprobs
|
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|
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Args:
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vllm_model: vLLM model fixture
|
||||
example_prompts: list of example prompts (test fixture)
|
||||
"""
|
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max_tokens = 5
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|
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sampling_params_logprobs_zero = SamplingParams(
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max_tokens=max_tokens, logprobs=0, prompt_logprobs=0, temperature=0.0
|
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)
|
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results_logprobs_zero = vllm_model.llm.generate(
|
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example_prompts, sampling_params=sampling_params_logprobs_zero
|
||||
)
|
||||
|
||||
for i in range(len(results_logprobs_zero)):
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# Check that there is one sample logprob dict for each
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# sample token
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logprobs = results_logprobs_zero[i].outputs[0].logprobs
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prompt_logprobs = results_logprobs_zero[i].prompt_logprobs
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sampled_token_ids = results_logprobs_zero[i].outputs[0].token_ids
|
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prompt_token_ids = results_logprobs_zero[i].prompt_token_ids
|
||||
assert logprobs is not None
|
||||
assert len(sampled_token_ids) == len(logprobs)
|
||||
assert results_logprobs_zero[i].outputs[0].cumulative_logprob is not None
|
||||
# Check that there is one prompt logprob dict for each
|
||||
# prompt token
|
||||
assert prompt_logprobs is not None
|
||||
assert len(prompt_token_ids) == len(prompt_logprobs)
|
||||
|
||||
|
||||
def test_all_logprobs(example_prompts):
|
||||
"""Engine should return all vocabulary logprobs and prompt logprobs
|
||||
|
||||
Args:
|
||||
example_prompts: list of example prompts (test fixture)
|
||||
"""
|
||||
runner = VllmRunner(
|
||||
"facebook/opt-125m",
|
||||
max_logprobs=-1,
|
||||
enable_prefix_caching=False,
|
||||
# 2 other llms alive during whole session
|
||||
gpu_memory_utilization=0.15,
|
||||
max_model_len=256,
|
||||
)
|
||||
|
||||
sampling_params_logprobs_all = SamplingParams(
|
||||
max_tokens=5, logprobs=-1, prompt_logprobs=-1
|
||||
)
|
||||
results_logprobs_all = runner.llm.generate(
|
||||
example_prompts, sampling_params=sampling_params_logprobs_all
|
||||
)
|
||||
vocab_size = runner.llm.llm_engine.model_config.get_vocab_size()
|
||||
|
||||
for i in range(len(results_logprobs_all)):
|
||||
logprobs = results_logprobs_all[i].outputs[0].logprobs
|
||||
prompt_logprobs = results_logprobs_all[i].prompt_logprobs
|
||||
assert logprobs is not None
|
||||
for logprob in logprobs:
|
||||
assert len(logprob) == vocab_size
|
||||
assert prompt_logprobs is not None
|
||||
assert prompt_logprobs[0] is None
|
||||
for prompt_logprob in prompt_logprobs[1:]:
|
||||
assert len(prompt_logprob) == vocab_size
|
||||
|
||||
|
||||
@pytest.mark.parametrize("logprobs_mode", get_args(LogprobsMode))
|
||||
def test_logprobs_mode(logprobs_mode: LogprobsMode):
|
||||
"""Test with LLM engine with different logprobs_mode.
|
||||
For logprobs, we should have non-positive values.
|
||||
For logits, we should expect at least one positive values.
|
||||
"""
|
||||
from vllm import LLM
|
||||
|
||||
llm = LLM(
|
||||
"facebook/opt-125m",
|
||||
max_logprobs=5,
|
||||
enable_prefix_caching=False,
|
||||
# 2 other llms alive during whole session
|
||||
gpu_memory_utilization=0.05,
|
||||
max_model_len=16,
|
||||
logprobs_mode=logprobs_mode,
|
||||
)
|
||||
vllm_sampling_params = SamplingParams(logprobs=1)
|
||||
results = llm.generate(["Hello world"], sampling_params=vllm_sampling_params)
|
||||
|
||||
total_token_with_logprobs = 0
|
||||
positive_values = 0
|
||||
for output in results[0].outputs:
|
||||
for logprobs in output.logprobs:
|
||||
for token_id in logprobs:
|
||||
logprob = logprobs[token_id]
|
||||
if logprobs_mode in ("raw_logprobs", "processed_logprobs"):
|
||||
assert logprob.logprob <= 0
|
||||
if logprob.logprob > 0:
|
||||
positive_values = positive_values + 1
|
||||
total_token_with_logprobs = total_token_with_logprobs + 1
|
||||
assert total_token_with_logprobs >= len(results[0].outputs)
|
||||
if logprobs_mode in ("raw_logits", "processed_logits"):
|
||||
assert positive_values > 0
|
||||
del llm
|
||||
|
||||
|
||||
@pytest.mark.parametrize("logprobs_mode", get_args(LogprobsMode))
|
||||
@pytest.mark.parametrize(
|
||||
"model_setup",
|
||||
[
|
||||
pytest.param(
|
||||
(
|
||||
"eagle",
|
||||
"meta-llama/Llama-3.2-1B-Instruct",
|
||||
"nm-testing/Llama3_2_1B_speculator.eagle3",
|
||||
),
|
||||
marks=large_gpu_mark(min_gb=32),
|
||||
),
|
||||
],
|
||||
)
|
||||
@pytest.mark.parametrize("top_logprobs", [0, 3])
|
||||
def test_spec_decode_logprobs(
|
||||
logprobs_mode: LogprobsMode,
|
||||
model_setup: tuple[str, str, str],
|
||||
top_logprobs: int,
|
||||
):
|
||||
"""Spec decode logprobs should match those of the base model.
|
||||
|
||||
Args:
|
||||
logprobs_mode: logprobs mode.
|
||||
model_setup: Spec decode method, base model name, and
|
||||
draft model name.
|
||||
"""
|
||||
from vllm import LLM
|
||||
|
||||
prompt = "Hello world " * 50
|
||||
sampling_params = SamplingParams(
|
||||
temperature=0, logprobs=top_logprobs, max_tokens=10, ignore_eos=False
|
||||
)
|
||||
method, model_name, spec_model_name = model_setup
|
||||
max_model_len = 256
|
||||
|
||||
# Run base LLM.
|
||||
ref_llm = LLM(
|
||||
model=model_name,
|
||||
max_logprobs=5,
|
||||
max_model_len=max_model_len,
|
||||
seed=42,
|
||||
logprobs_mode=logprobs_mode,
|
||||
gpu_memory_utilization=0.4,
|
||||
)
|
||||
ref_results = ref_llm.generate([prompt], sampling_params)
|
||||
# Collect logprobs outputs from reference LLM.
|
||||
ref_logprobs = []
|
||||
for output in ref_results[0].outputs:
|
||||
for logprobs in output.logprobs:
|
||||
for token_id in logprobs:
|
||||
ref_logprobs.append(logprobs[token_id])
|
||||
del ref_llm
|
||||
torch.cuda.empty_cache()
|
||||
cleanup_dist_env_and_memory()
|
||||
|
||||
# Run spec decode LLM.
|
||||
spec_llm = LLM(
|
||||
model_name,
|
||||
speculative_config={
|
||||
"method": method,
|
||||
"model": spec_model_name,
|
||||
"num_speculative_tokens": 3,
|
||||
"max_model_len": max_model_len,
|
||||
},
|
||||
max_logprobs=5,
|
||||
max_model_len=max_model_len,
|
||||
seed=42,
|
||||
logprobs_mode=logprobs_mode,
|
||||
gpu_memory_utilization=0.4,
|
||||
# Force prefill chunking
|
||||
enable_chunked_prefill=True,
|
||||
max_num_batched_tokens=32,
|
||||
)
|
||||
spec_results = spec_llm.generate([prompt], sampling_params)
|
||||
# Collect logprobs outputs from spec decode LLM.
|
||||
spec_logprobs = []
|
||||
for output in spec_results[0].outputs:
|
||||
for logprobs in output.logprobs:
|
||||
for token_id in logprobs:
|
||||
spec_logprobs.append(logprobs[token_id])
|
||||
del spec_llm
|
||||
torch.cuda.empty_cache()
|
||||
cleanup_dist_env_and_memory()
|
||||
|
||||
# Per-token logprobs are expected to be the same.
|
||||
assert len(ref_logprobs) == len(spec_logprobs)
|
||||
for ref_logprob, spec_logprob in zip(ref_logprobs, spec_logprobs):
|
||||
assert math.isclose(
|
||||
ref_logprob.logprob, spec_logprob.logprob, rel_tol=5e-2, abs_tol=1e-1
|
||||
)
|
||||
assert ref_logprob.rank == spec_logprob.rank
|
||||
assert ref_logprob.decoded_token == spec_logprob.decoded_token
|
||||
|
||||
|
||||
def test_prompt_logprobs_with_chunking_and_preemption():
|
||||
"""Test that prompt logprobs are correctly returned when using
|
||||
both chunked prefill and preemption.
|
||||
|
||||
This test ensures that the num_prompt_logprobs tracking persists
|
||||
across preemptions and prefill chunks.
|
||||
"""
|
||||
|
||||
# Create prompts that will trigger chunking and preemption
|
||||
prompts = [
|
||||
"The following numbers of the sequence "
|
||||
+ ", ".join(str(i) for i in range(10))
|
||||
+ " are:",
|
||||
"In one word, the capital of France is ",
|
||||
] + [f"Tell me about the number {i}: " for i in range(32)]
|
||||
|
||||
sampling_params = SamplingParams(
|
||||
temperature=0.0,
|
||||
max_tokens=40,
|
||||
min_tokens=20,
|
||||
prompt_logprobs=2, # Request prompt logprobs
|
||||
)
|
||||
|
||||
with VllmRunner(
|
||||
"Qwen/Qwen3-0.6B",
|
||||
max_model_len=512,
|
||||
enable_chunked_prefill=True,
|
||||
max_num_batched_tokens=48, # Force prefill chunking
|
||||
num_gpu_blocks_override=32, # Force preemptions
|
||||
disable_log_stats=False,
|
||||
gpu_memory_utilization=0.25,
|
||||
) as vllm_model:
|
||||
metrics_before = vllm_model.llm.get_metrics()
|
||||
|
||||
# Generate with prompt logprobs using generate_w_logprobs which
|
||||
# returns (output_ids, output_str, output_logprobs, prompt_logprobs)
|
||||
outputs = vllm_model.generate_w_logprobs(
|
||||
prompts, sampling_params=sampling_params, include_prompt_token_ids=True
|
||||
)
|
||||
|
||||
# Verify that all outputs have prompt logprobs
|
||||
for i, output in enumerate(outputs):
|
||||
_, _, _, prompt_token_ids, prompt_logprobs = output
|
||||
assert prompt_logprobs is not None and len(prompt_logprobs) > 0, (
|
||||
f"Output {i} missing prompt logprobs"
|
||||
)
|
||||
assert len(prompt_logprobs) == len(prompt_token_ids), (
|
||||
"Unexpected number of prompt logprob positions"
|
||||
)
|
||||
|
||||
# Each position should have the requested number of logprobs
|
||||
for pos, logprobs_dict in enumerate(prompt_logprobs):
|
||||
if logprobs_dict is not None: # First token may be None
|
||||
assert (
|
||||
sampling_params.prompt_logprobs
|
||||
<= len(logprobs_dict)
|
||||
<= sampling_params.prompt_logprobs + 1
|
||||
), (
|
||||
f"Output {i} position {pos} has {len(logprobs_dict)} "
|
||||
f"logprobs, expected {sampling_params.prompt_logprobs}"
|
||||
)
|
||||
|
||||
# Check that we actually had preemptions
|
||||
metrics_after = vllm_model.llm.get_metrics()
|
||||
preemptions_before = next(
|
||||
(m.value for m in metrics_before if m.name == "vllm:num_preemptions"), 0
|
||||
)
|
||||
preemptions_after = next(
|
||||
(m.value for m in metrics_after if m.name == "vllm:num_preemptions"), 0
|
||||
)
|
||||
preemptions = preemptions_after - preemptions_before
|
||||
assert preemptions > 0, "Test did not trigger any preemptions"
|
||||
|
||||
print(f"Test passed with {preemptions} preemptions")
|
||||
Reference in New Issue
Block a user