The CP in-seq NSA indexer path was constructing a CUDA validity mask around each fp8_mqa_logits call, synchronizing it back with .item(), and then rebuilding small CUDA tensors before topk. The valid rows are always a contiguous prefix because ke_offset is monotonic, so the count can be derived from existing CP metadata and the path can use slices instead of boolean gather/scatter. RAGGED topk now reuses the zero row-start vector as the per-row offset override for the single-segment case to avoid cumsum/repeat_interleave metadata kernels after MQA. Constraint: CP shared KV prefill still needs to preserve prev/next causal visibility and topk transform semantics. Rejected: Add a new Triton range-builder first | the Python-side synchronization and boolean indexing were the larger immediate risk, and kernel work should be profiled after this smaller change. Confidence: medium Scope-risk: moderate Directive: Do not reintroduce GPU mask .item() or CPU-created CUDA tensors in the fp8_mqa_logits hot path without profiler evidence. Tested: python3 -m py_compile python/sglang/srt/layers/attention/nsa/nsa_indexer.py test/registered/unit/layers/test_nsa_cp_utils.py Tested: g0034 docker /sgl-workspace/sglang-tai python3 test/registered/unit/layers/test_nsa_cp_utils.py -> Ran 22 tests OK Not-tested: full GLM5 PD server throughput/profiler run
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.