[mtp] add rejection sampling for speculative decoding (#26312)

Co-authored-by: lyc508653 <lyc508653@alibaba-inc.com> Co-authored-by: Qiaolin-Yu <liin1211@outlook.com> Co-authored-by: Huiqiang Jiang <30883354+iofu728@users.noreply.github.com> Co-authored-by: Yi Zhang <25844240+yizhang2077@users.noreply.github.com> Co-authored-by: Yizhong Cao <114661107+cao1zhg@users.noreply.github.com>
2026-06-20 15:10:42 -07:00
parent 95fb1ef697
commit f42ec350b4
11 changed files with 566 additions and 20 deletions
@@ -0,0 +1,91 @@
+import unittest
+from types import SimpleNamespace
+
+import requests
+
+from sglang.srt.environ import envs
+from sglang.srt.utils import kill_process_tree
+from sglang.test.ci.ci_register import register_cuda_ci
+from sglang.test.run_eval import run_eval
+from sglang.test.test_utils import (
+    DEFAULT_URL_FOR_TEST,
+    CustomTestCase,
+    is_in_ci,
+    popen_launch_server,
+    write_github_step_summary,
+)
+
+register_cuda_ci(est_time=300, stage="base-b", runner_config="2-gpu-large")
+
+QWEN35_MODEL = "Qwen/Qwen3.5-9B"
+SERVER_LAUNCH_TIMEOUT = 600
+
+
+class TestQwen35EagleRS(CustomTestCase):
+    @classmethod
+    def setUpClass(cls):
+        cls.model = QWEN35_MODEL
+        cls.base_url = DEFAULT_URL_FOR_TEST
+        other_args = [
+            "--trust-remote-code",
+            "--tp",
+            "2",
+            "--speculative-algorithm",
+            "NEXTN",
+            "--speculative-num-steps",
+            "3",
+            "--speculative-eagle-topk",
+            "1",
+            "--speculative-num-draft-tokens",
+            "4",
+            "--speculative-use-rejection-sampling",
+            "--mem-fraction-static",
+            "0.8",
+            "--disable-radix-cache",
+        ]
+        with envs.SGLANG_ENABLE_ASYNC_ASSERT.override(True):
+            cls.process = popen_launch_server(
+                cls.model,
+                cls.base_url,
+                timeout=SERVER_LAUNCH_TIMEOUT,
+                other_args=other_args,
+            )
+
+    @classmethod
+    def tearDownClass(cls):
+        kill_process_tree(cls.process.pid)
+
+    def test_a_gsm8k(self):
+        requests.get(self.base_url + "/flush_cache")
+
+        args = SimpleNamespace(
+            base_url=self.base_url,
+            model=self.model,
+            eval_name="gsm8k",
+            api="completion",
+            max_tokens=512,
+            num_examples=200,
+            num_threads=128,
+        )
+        metrics = run_eval(args)
+        print(f"{metrics=}")
+
+        server_info = requests.get(self.base_url + "/server_info").json()
+        avg_spec_accept_length = server_info["internal_states"][0][
+            "avg_spec_accept_length"
+        ]
+        print(f"{avg_spec_accept_length=}")
+
+        if is_in_ci():
+            write_github_step_summary(
+                f"### test_gsm8k (qwen3.5-9b nextn rs)\n"
+                f'{metrics["score"]=:.3f}\n'
+                f"{avg_spec_accept_length=:.2f}\n"
+            )
+
+        self.assertGreater(metrics["score"], 0.8)
+        self.assertGreater(avg_spec_accept_length, 2.5)
+
+
+if __name__ == "__main__":
+    unittest.main()