Files
sglang/test/registered/unit
laoyao0822 a638d71d53 Avoid PAGED topk metadata scans after MQA
Prefill CP shared KV uses the PAGED fused topk path, but topk_transform still built RAGGED topk offsets before dispatching by method. That introduced cumsum/repeat_interleave work after MQA, showing up as DeviceScanInitKernel and host/device traffic in profiles even though PAGED topk only needs cu_seqlens_q. Move metadata construction into the selected branch and pass precomputed single-segment CP cu_seqlens overrides from NSA CP metadata.

Constraint: PAGED fused topk needs cu_seqlens_q but does not consume topk_indices_offset.\nRejected: Add a kernel to fuse repeat_interleave for PAGED | the offset is unused in the current path, so avoiding it is cheaper and safer.\nConfidence: high\nScope-risk: narrow\nDirective: Do not reintroduce unconditional topk_indices_offset construction in topk_transform; keep RAGGED-only metadata on the RAGGED branch.\nTested: python -m py_compile for modified files locally; g0034 container python3 -m py_compile for modified files; g0034 container python3 test/registered/unit/layers/test_nsa_cp_utils.py ran 23 tests OK.\nNot-tested: Full server profile after restart; full SGLang test suite.
2026-05-03 23:08:17 +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.