leavelet
54c056af83
专题 S1 (design: docs_internal/perf/prefill-compute-intensity-plan.md S1.0-S1.11). A batch containing a chunked prefill request has been forced to bs=1 by the CP gate, so every chunk of a long prompt monopolizes a forward while short-extend cache-hit continuations queue — the direct cause of the replay TTFT tail (p90 19.3s / p99 49.2s at 91.8% cache hit). Yet mixed chunk batches already occur today (a freshly-chunked request keeps earlier-admitted small requests), proving the CP forward path is mixed-chunk-safe; only admission was asymmetric. Three changes, the first flag-independent: - add_chunked_req now seeds the budget with the chunk's TRUE prefix (was 0), so the CP cached tally and the buffer estimator's mqa_logits k_rows see the chunk's footprint before any later request is admitted (landmine D1). - New SGLANG_CP_PREFILL_MIX_CHUNKED (default OFF): with it on, the gate admits requests after a chunked one and lets the existing CP caps (extend / cached / buffer, now correctly seeded) bound the batch — a FULL chunk still ends the scan by consuming the chunk-clamped extend cap; only a tail chunk leaves headroom. A chunked prefix that is not page-aligned (rare sub-page final-chunk tail) keeps its batch solo (the CP page-aligned split would fail-fast otherwise). - The symm staging capacity identity (admission extend cap + request slack == staging pages) is asserted when the flag is on, locking the coupling the design relies on (plan doc S1.4 I2). Tests: 4 new adder units (budget seeding; tail chunk admits followers; full chunk solo by budget; non-aligned prefix solo); the 8-rank byte-exactness scenario gains a chunk-shaped request (2048-token page-aligned carried prefix + 512 extend) — all four phases (legacy/v2/symm/prefetch) byte-identical on g0033. Known pre-existing cross-file pollution noted in problems.md P16. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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.