Files
sglang/test/registered/unit
laoyao0822 50d0008705 Enable batched CP shared-KV current reuse correctness
Batch-size > 1 cache-hit traffic must not lose the current/partial-current reuse fast path. This change extends the target MLA/index sync-correct path to validate batched current suffix rows, compose page-aligned prefix spans, and route batched index top-k through current-only or partial-current reuse without falling back to scalar guards.\n\nThe implementation keeps page as the minimum cache unit: prefix cache coverage is page-aligned, while current suffix rows are sliced by valid extend lengths so padded tail rows are not exposed to attention. The index top-k batch path now mirrors the single-request contract: current-only reuses current index KV directly, partial-current materializes once and shares the dense buffer across request segments.\n\nConstraint: CP shared-KV supports in-seq zigzag only; round-robin remains fail-fast for shared-KV.\nConstraint: No new collectives are introduced; this is a sync correctness path, not a new communication scheme.\nRejected: Keep bs>1 current_index_kv fail-fast | disables the cache-hit path that W4 is meant to restore.\nRejected: Pad requests to a common batch length | violates the page-granular contract and exposes padded tails to consumers.\nConfidence: medium\nScope-risk: moderate\nDirective: Do not reintroduce batch_size_not_one or batch_gt1 current-reuse guards without proving an equivalent batched fast path exists.\nTested: Local py_compile for touched runtime/test files.\nTested: Remote g0034 pytest test_nsa_cp_utils.py test_cp_shared_kv_runtime.py => 157 passed, 5 warnings, 2 subtests passed.\nTested: Remote g0034 pytest test_cp_shared_kv_layout.py => 27 passed, 3 warnings.\nNot-tested: Full ETE with live traffic; CUDA kernel-backed batched descriptors; L1 prefetch, HiCache load/backup, and draft/EAGLE bs>1 current reuse.
2026-06-03 07:06:21 +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.