[CI/CD] fix: test metric tag setting

[llsj14]

#13716
There are some test failures in test_metrics.py. This PR aims to fix these errors.

[2025-02-23T04:29:50Z] =========================== short test summary info ============================
--
  | [2025-02-23T04:29:50Z] FAILED metrics/test_metrics.py::test_metric_set_tag_model_name[None-float-distilbert/distilgpt2] - AssertionError: Metrics tag model_name is wrong! expect: 'distilbert/distilgpt2'
  | [2025-02-23T04:29:50Z]   actual: 'distilbert/distilgpt2'
  | [2025-02-23T04:29:50Z] assert 'distilbert/distilgpt2' == 's3://vllm-ci...rt/distilgpt2'
  | [2025-02-23T04:29:50Z]
  | [2025-02-23T04:29:50Z]   - s3://vllm-ci-model-weights/distilbert/distilgpt2
  | [2025-02-23T04:29:50Z]   + distilbert/distilgpt2
  | [2025-02-23T04:29:50Z] FAILED metrics/test_metrics.py::test_metric_set_tag_model_name[served_model_name1-float-distilbert/distilgpt2] - AssertionError: Metrics tag model_name is wrong! expect: 'distilbert/distilgpt2'
  | [2025-02-23T04:29:50Z]   actual: 'distilbert/distilgpt2'
  | [2025-02-23T04:29:50Z] assert 'distilbert/distilgpt2' == 's3://vllm-ci...rt/distilgpt2'
  | [2025-02-23T04:29:50Z]
  | [2025-02-23T04:29:50Z]   - s3://vllm-ci-model-weights/distilbert/distilgpt2
  | [2025-02-23T04:29:50Z]   + distilbert/distilgpt2
  | [2025-02-23T04:29:50Z] FAILED metrics/test_metrics.py::test_engine_log_metrics_regression[False-4-half-distilbert/distilgpt2] - AssertionError: Metrics should be collected
  | [2025-02-23T04:29:50Z] assert None == 8
  | [2025-02-23T04:29:50Z] =================== 3 failed, 17 passed in 527.27s (0:08:47) ===================

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[llsj14]

@khluu @DarkLight1337 Could you check this PR please?
I'm having some troubles in my PR related to test_metrics.py.

[khluu]

where do you see the failures? This test passed on latest commit on main https://buildkite.com/vllm/ci/builds/14022#0195312e-1004-462a-984a-954af4465df4

[llsj14]

I'm having test failures in this PR.
#11966
https://buildkite.com/vllm/fastcheck/builds/14842#019530e8-2776-4a34-8866-9f0d571cad94

[llsj14]

After this change, one test failure was resolved, but there are still test failures, so I'm investigating.
This is also an issue I encountered in the previous PR.

[2025-02-23T06:05:14Z] metrics/test_metrics.py:219:
--
  | [2025-02-23T06:05:14Z] _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
  | [2025-02-23T06:05:14Z]
  | [2025-02-23T06:05:14Z] model = 's3://vllm-ci-model-weights/distilbert/distilgpt2'
  | [2025-02-23T06:05:14Z] engine = <vllm.engine.llm_engine.LLMEngine object at 0x7fa8f1f259d0>
  | [2025-02-23T06:05:14Z] disable_log_stats = False, num_requests = 8
  | [2025-02-23T06:05:14Z]
  | [2025-02-23T06:05:14Z]     def assert_metrics(model: str, engine: LLMEngine, disable_log_stats: bool,
  | [2025-02-23T06:05:14Z]                        num_requests: int) -> None:
  | [2025-02-23T06:05:14Z]         if disable_log_stats:
  | [2025-02-23T06:05:14Z]             with pytest.raises(AttributeError):
  | [2025-02-23T06:05:14Z]                 _ = engine.stat_loggers
  | [2025-02-23T06:05:14Z]         else:
  | [2025-02-23T06:05:14Z]             assert (engine.stat_loggers
  | [2025-02-23T06:05:14Z]                     is not None), "engine.stat_loggers should be set"
  | [2025-02-23T06:05:14Z]             # Ensure the count bucket of request-level histogram metrics matches
  | [2025-02-23T06:05:14Z]             # the number of requests as a simple sanity check to ensure metrics are
  | [2025-02-23T06:05:14Z]             # generated
  | [2025-02-23T06:05:14Z]             labels = {'model_name': model}
  | [2025-02-23T06:05:14Z]             request_histogram_metrics = [
  | [2025-02-23T06:05:14Z]                 "vllm:e2e_request_latency_seconds",
  | [2025-02-23T06:05:14Z]                 "vllm:request_prompt_tokens",
  | [2025-02-23T06:05:14Z]                 "vllm:request_generation_tokens",
  | [2025-02-23T06:05:14Z]                 "vllm:request_params_n",
  | [2025-02-23T06:05:14Z]                 "vllm:request_params_max_tokens",
  | [2025-02-23T06:05:14Z]             ]
  | [2025-02-23T06:05:14Z]             for metric_name in request_histogram_metrics:
  | [2025-02-23T06:05:14Z]                 metric_value = REGISTRY.get_sample_value(f"{metric_name}_count",
  | [2025-02-23T06:05:14Z]                                                          labels)
  | [2025-02-23T06:05:14Z] >               assert (
  | [2025-02-23T06:05:14Z]                     metric_value == num_requests), "Metrics should be collected"
  | [2025-02-23T06:05:14Z] E               AssertionError: Metrics should be collected
  | [2025-02-23T06:05:14Z] E               assert None == 8
  | [2025-02-23T06:05:14Z]
  | [2025-02-23T06:05:14Z] metrics/test_metrics.py:384: AssertionError
  | [2025-02-23T06:05:14Z] =========================== short test summary info ============================
  | [2025-02-23T06:05:14Z] FAILED metrics/test_metrics.py::test_engine_log_metrics_regression[False-4-half-distilbert/distilgpt2] - AssertionError: Metrics should be collected
  | [2025-02-23T06:05:14Z] assert None == 8

[khluu]

After this change, one test failure was resolved, but there are still test failures, so I'm investigating. This is also an issue I encountered in the previous PR.

Yea can you merge that PR with main? The fix for that test was merged to main a few hours ago

[llsj14]

Yeah, I merged the latest commit from #13278.

[llsj14]

I still have some failures while running test_engine_log_metrics_regression.

[llsj14]

It seems everything was fixed by this commit.
Thank you, @khluu!