Files
sglang/test/registered/unit
laoyao0822 81eb138a26 Avoid CP HiCache owner-lane planning stalls during load-back
CP HiCache load-back eviction planning previously recomputed per-owner page counts from node token tensors while scanning evictable leaves. Under shared-KV pressure this can put scheduler-side planning onto an expensive tensor-padding path and stall before load_back can complete.

This stores per-CP-size owner page counts on CP HiCache metadata and uses that CPU metadata for backed/resident CP nodes. Streaming abort handling also accepts int-like status codes so abort responses do not crash on .name/.value access. Temporary debug runbooks remain ignored.

Unnecessary prefill hot-path timing logs were removed before commit; owner-lane eviction now keeps warning-level output for slow planning, insufficient eviction, or remaining deficits only.

Constraint: CP shared-KV cache residency is page-owner based and already records page owners in CpHiCacheNodeMetadata.
Rejected: Keep verbose prefill/owner-lane timing logs | they proved the issue but add hot-path noise after validation.
Confidence: medium
Scope-risk: moderate
Directive: Do not reintroduce tensor-derived owner counting on CP HiCache backed nodes without measuring scheduler CPU/GPU sync cost.
Tested: python -m py_compile python/sglang/srt/mem_cache/hiradix_cache.py python/sglang/srt/entrypoints/openai/serving_base.py python/sglang/srt/entrypoints/openai/serving_chat.py python/sglang/srt/entrypoints/openai/serving_completions.py test/registered/unit/mem_cache/test_cp_hicache_load_back_owner_lanes.py
Tested: git diff --check
Not-tested: Local pytest collection is blocked by missing starlette dependency.
Not-tested: Full ETE after log cleanup; previous pre-cleanup ETE replay reached 136098.82 prompt tok/s without killing prefill.
2026-06-09 06:55:39 +08:00
..

Unit Tests

Component-level tests that do not launch a server or load model weights. Tests can use CPU or GPU — the key criterion is no server process.

Quick Start

  1. Find the source file under python/sglang/srt/.
  2. Create the corresponding test here, mirroring the source tree:
    srt/mem_cache/radix_cache.py       →  unit/mem_cache/test_radix_cache.py
    srt/sampling/sampling_params.py    →  unit/sampling/test_sampling_params.py
    
  3. Register for CI at the top of the file (after imports, before test classes):
    from sglang.test.ci.ci_register import register_cpu_ci
    register_cpu_ci(est_time=5, suite="stage-a-test-cpu")
    # or: register_cuda_ci(est_time=10, suite="stage-b-test-1-gpu-small")
    
  4. Run locally:
    pytest test/registered/unit/ -v            # all unit tests
    pytest test/registered/unit/mem_cache/ -v  # one module
    
  5. Run with coverage:
    # summary
    pytest test/registered/unit/ --cov --cov-config=.coveragerc -v
    
    # PR incremental check (require ≥60% on changed lines)
    pytest test/registered/unit/ --cov --cov-config=.coveragerc --cov-report=xml
    diff-cover coverage.xml --compare-branch=origin/main --fail-under=60
    

Example

"""Unit tests for <module> — no server, no model loading."""

from sglang.test.ci.ci_register import register_cpu_ci

register_cpu_ci(est_time=5, suite="stage-a-test-cpu")

import unittest

from sglang.srt.<module> import TargetClass
from sglang.test.test_utils import CustomTestCase


class TestTargetClass(CustomTestCase):
    def test_basic_behavior(self):
        obj = TargetClass(...)
        self.assertEqual(obj.method(), expected)


if __name__ == "__main__":
    unittest.main()

Rules

  • No popen_launch_server() or Engine(...).
  • No model weight loading.
  • Use CustomTestCase (from sglang.test.test_utils, adds CI retry).
  • Use unittest.mock for dependencies that are expensive to construct.