Files
sglang/test/registered/unit
laoyao0822 96158fa110 Bound overlap prefill to one pending CP batch
CP shared-KV batch planning needs the immediately previous prepared batch to remain visible as a virtual prefix, but launching another batch before processing that result can leave multiple prepared plans racing against radix insertion. The event loop now processes the previous result after planning the current batch and before launching it, preserving one-batch lookback without accumulating deeper overlap state.

Constraint: CP HiCache prepared batch views are inserted during process_batch_result, not at forward launch.

Rejected: Process previous result before planning current batch | loses visibility of the previous pending prepared plan needed by current planning.

Confidence: medium

Scope-risk: moderate

Directive: Do not increase non-PP overlap depth for CP shared-KV without adding pending-radix reservation semantics.

Tested: Remote cjy-glm5-new pytest test/registered/unit/disaggregation/test_overlap_disagg_prefill_event_loop.py test/registered/unit/disaggregation/test_overlap_disagg_decode_event_loop.py

Not-tested: Full E2E latency impact of reduced overlap depth.
(cherry picked from commit 7df8723eee8203e9e334b229178e3f8bac61396a)
2026-06-19 06:14:20 +00:00
..

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.