Files
sglang/test/registered/unit
laoyao0822 c3fc3ff752 Stabilize CP shared-KV prefetch around draft cache hits
Cache-hit EAGLE/NextN draft extends can enter the draft DeepEP MoE immediately after CP shared-KV attention. The partial current-reuse path is kept for target layers, but draft cache-hit suffixes now use full materialization until draft has an explicit same-layer reuse contract. Next-layer MLA/index prefetch is also gated by the actual model depth, so the single-layer draft model does not enqueue unused next-layer async work.

The temporary stage traces used to isolate the hang are removed. The retained draft current-reuse fallback is a bounded warning because it changes the runtime path intentionally.

Constraint: EAGLE/NextN has one executable draft layer and mirrors target KV state.

Rejected: Keep partial current reuse for draft cache-hit suffixes | reproduced hangs at draft layer0 before DeepEP MoE completion.

Rejected: Keep temporary stage traces | useful for diagnosis but too noisy for normal runs.

Confidence: medium

Scope-risk: moderate

Directive: Do not re-enable draft cache-hit partial current reuse without an explicit draft same-layer reuse contract and ETE validation with CP shared KV + HiCache + EAGLE.

Tested: py_compile on edited Python files; git diff --check; temp trace grep returned no matches.

Not-tested: Local targeted pytest is blocked by missing pybase64 in this environment; full ETE after log cleanup not run.
2026-05-29 00:33:41 +08:00
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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.