[PD] Support decode retract and update decode.py (#7196)

test/srt/test_disaggregation.py

@@ -469,5 +469,132 @@ class TestDisaggregationMooncakeSpec(CustomTestCase):
         self.assertGreater(metrics["accuracy"], 0.20)
 
 
+class TestDisaggregationSimulatedRetract(CustomTestCase):
+    @classmethod
+    def setUpClass(cls):
+        os.environ["SGLANG_TEST_RETRACT"] = "true"
+        cls.model = DEFAULT_MODEL_NAME_FOR_TEST
+        parsed_url = urlparse(DEFAULT_URL_FOR_TEST)
+        cls.base_host = parsed_url.hostname
+        base_port = str(parsed_url.port)
+        cls.lb_port = base_port
+        cls.prefill_port = f"{int(base_port) + 100}"
+        cls.decode_port = f"{int(base_port) + 200}"
+        cls.prefill_url = f"http://{cls.base_host}:{cls.prefill_port}"
+        cls.decode_url = f"http://{cls.base_host}:{cls.decode_port}"
+        cls.lb_url = f"http://{cls.base_host}:{cls.lb_port}"
+        print(f"{cls.base_host=} {cls.lb_port=} {cls.prefill_port=} {cls.decode_port=}")
+
+        # Non blocking start servers
+        cls.start_prefill()
+        cls.start_decode()
+
+        # Block until both
+        cls.wait_server_ready(cls.prefill_url + "/health")
+        cls.wait_server_ready(cls.decode_url + "/health")
+
+        lb_command = [
+            "python3",
+            "-m",
+            "sglang.srt.disaggregation.mini_lb",
+            "--prefill",
+            cls.prefill_url,
+            "--decode",
+            cls.decode_url,
+            "--host",
+            cls.base_host,
+            "--port",
+            cls.lb_port,
+        ]
+
+        print("Starting load balancer:", " ".join(lb_command))
+        cls.process_lb = subprocess.Popen(
+            lb_command, stdout=subprocess.PIPE, stderr=subprocess.PIPE
+        )
+        cls.wait_server_ready(cls.lb_url + "/health")
+
+    @classmethod
+    def start_prefill(cls):
+        prefill_args = [
+            "--trust-remote-code",
+            "--disaggregation-mode",
+            "prefill",
+            "--tp",
+            "1",
+            "--disaggregation-ib-device",
+            "mlx5_roce0",
+        ]
+        cls.process_prefill = popen_launch_pd_server(
+            cls.model,
+            cls.prefill_url,
+            timeout=DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
+            other_args=prefill_args,
+        )
+
+    @classmethod
+    def start_decode(cls):
+        decode_args = [
+            "--trust-remote-code",
+            "--disaggregation-mode",
+            "decode",
+            "--tp",
+            "1",
+            "--base-gpu-id",
+            "1",
+            "--disaggregation-ib-device",
+            "mlx5_roce1",
+        ]
+        cls.process_decode = popen_launch_pd_server(
+            cls.model,
+            cls.decode_url,
+            timeout=DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
+            other_args=decode_args,
+        )
+
+    @classmethod
+    def wait_server_ready(cls, url, timeout=DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH):
+        start_time = time.perf_counter()
+        while True:
+            try:
+                response = requests.get(url)
+                if response.status_code == 200:
+                    print(f"Server {url} is ready")
+                    return
+            except Exception:
+                pass
+
+            if time.perf_counter() - start_time > timeout:
+                raise RuntimeError(f"Server {url} failed to start in {timeout}s")
+            time.sleep(1)
+
+    @classmethod
+    def tearDownClass(cls):
+        os.environ.pop("SGLANG_TEST_RETRACT")
+        for process in [cls.process_lb, cls.process_decode, cls.process_prefill]:
+            if process:
+                try:
+                    kill_process_tree(process.pid)
+                except Exception as e:
+                    print(f"Error killing process {process.pid}: {e}")
+
+        # wait for 5 seconds
+        time.sleep(5)
+
+    def test_gsm8k(self):
+        args = SimpleNamespace(
+            num_shots=5,
+            data_path=None,
+            num_questions=200,
+            max_new_tokens=512,
+            parallel=128,
+            host=f"http://{self.base_host}",
+            port=int(self.lb_port),
+        )
+        metrics = run_eval_few_shot_gsm8k(args)
+        print(f"Evaluation metrics: {metrics}")
+
+        self.assertGreater(metrics["accuracy"], 0.62)
+
+
 if __name__ == "__main__":
     unittest.main()