laoyao0822
3a43727216
CP shared-KV bs>1 batching was only bounded by request count, extend tokens, and cached tokens. That left temporary GPU buffers such as MLA/index materialization, remap metadata, logits windows, and transfer descriptors implicit, and raw extend-token limits could exceed the active chunked-prefill budget.\n\nThis adds an explicit max-buffer-size admission gate with a CPU-only stream-aware estimator, wires it through PrefillAdder/Scheduler, performs a startup CUDA smoke allocation when configured, and reports the estimate in the scheduler admission benchmark. When chunked prefill is active, the effective CP extend-token limit is capped by the current chunk budget so the CP path does not advertise unreachable batch capacity or lift max-prefill-tokens too far.\n\nConstraint: Admission estimation must stay CPU-only on the scheduler hot path; CUDA allocation is limited to startup smoke checking.\nConstraint: Single oversized requests must still be allowed to run alone to avoid scheduler deadlock.\nRejected: Rely only on --max-prefill-tokens | it does not reliably bound the first oversized request and does not model cache-hit/load-back pressure.\nRejected: Let CP extend limit exceed chunked-prefill size | it creates an unreachable effective capacity and misleading budget lift.\nConfidence: medium\nScope-risk: moderate\nDirective: If bs>1 L1 prefetch is enabled later, update CPSharedKVPrefillBufferEstimatorContext.bs_gt1_l1_prefetch_enabled and include the live prefetch dense buffers in overlap windows.\nTested: local py_compile for touched files\nTested: local PYTHONPATH=python pytest -q test/registered/unit/managers/test_cp_shared_kv_prefill_buffer_estimator.py (4 passed)\nTested: remote cjy-glm5-new targeted pytest for new server_args, PrefillAdder, estimator, and benchmark cases (10 passed)\nTested: remote cjy-glm5-new PYTHONPATH=python pytest -q test/registered/unit/managers/test_cp_shared_kv_prefill_buffer_estimator.py test/registered/unit/managers/test_prefill_adder.py test/registered/unit/managers/test_prefill_scheduler_admission_bench.py (29 passed before chunk cap, then test_prefill_adder.py 21 passed after chunk cap)\nNot-tested: full server_args suite because existing TestPrepareServerArgs tries to reach HuggingFace and fails under container DNS/network\nNot-tested: GLM5 ETE smoke with --cp-shared-kv-prefill-max-buffer-size
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
- Find the source file under
python/sglang/srt/. - 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 - 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") - Run locally:
pytest test/registered/unit/ -v # all unit tests pytest test/registered/unit/mem_cache/ -v # one module - 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()orEngine(...). - No model weight loading.
- Use
CustomTestCase(fromsglang.test.test_utils, adds CI retry). - Use
unittest.mockfor dependencies that are expensive to construct.