leaveletandClaude Fable 5
698a3e2431
dfa168abe9made duplicate ack completion idempotent at the consumer (writing_check), which is correct and lock-balance-safe but masks the producer invariant breach: two acks can only coexist for one radix registration when an ack is orphaned in ack_write_queue after a rollback cleared ongoing_write_through/pending_host_backups, re-opening the _node_host_write_pending guard for a fresh registration. _rollback_pending_backup (write_backup's exception path) was the one rollback that did not scrub the node's acks — and it also left a half-submitted layer-write state alive, which later forwards would keep driving, writing D2H into host slots the rollback had already evicted. Close the invariant structurally: - reserve_write_cp refuses (HiCacheWriteFailure, the existing skip-this-round path both callers already handle) when the node still has an undrained final ack, computed by scanning the small ack queue — no new state to keep in sync. - _rollback_pending_backup now cancels the pending layer-write state (write-stream sync so in-flight per-layer copies finish before the host slots are evicted) and scrubs the node's queued acks via the scrub factored out of _rollback_prepared_cp_backup. - The consumer-side duplicate guard fromdfa168abe9is kept as defense in depth. 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.