[Feat] Support FlashMLA backend with MTP and FP8 KV cache (#6109)

Co-authored-by: Yingyi <yingyihuang2000@outlook.com>
Co-authored-by: neiltian <neiltian@tencent.com>
Co-authored-by: lukec <118525388+sleepcoo@users.noreply.github.com>
Co-authored-by: kexueyu <kexueyu@tencent.com>
Co-authored-by: vincentmeng <vincentmeng@tencent.com>
Co-authored-by: pengmeng <pengmeng@tencent.com>

test/srt/test_flashmla.py

@@ -6,6 +6,7 @@ python3 test/srt/test_flashmla.py
 import unittest
 from types import SimpleNamespace
 
+import requests
 import torch
 
 from sglang.srt.utils import kill_process_tree
@@ -14,6 +15,7 @@ from sglang.test.test_utils import (
     DEFAULT_MODEL_NAME_FOR_TEST_MLA,
     DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
     DEFAULT_URL_FOR_TEST,
+    CustomTestCase,
     is_in_ci,
     popen_launch_server,
     run_bench_one_batch,
@@ -81,5 +83,71 @@ class TestFlashMLAAttnLatency(unittest.TestCase):
             self.assertGreater(output_throughput, 100)
 
 
+class TestFlashMLAMTP(CustomTestCase):
+    @classmethod
+    def setUpClass(cls):
+        cls.model = "lmsys/sglang-ci-dsv3-test"
+        cls.base_url = DEFAULT_URL_FOR_TEST
+        other_args = ["--trust-remote-code"]
+        if torch.cuda.is_available() and torch.version.cuda:
+            other_args.extend(
+                [
+                    "--cuda-graph-max-bs",
+                    "4",
+                    "--disable-radix",
+                    "--enable-torch-compile",
+                    "--torch-compile-max-bs",
+                    "1",
+                    "--speculative-algorithm",
+                    "EAGLE",
+                    "--speculative-draft",
+                    "lmsys/sglang-ci-dsv3-test-NextN",
+                    "--speculative-num-steps",
+                    "1",
+                    "--speculative-eagle-topk",
+                    "1",
+                    "--speculative-num-draft-tokens",
+                    "2",
+                    "--attention-backend",
+                    "flashmla",
+                ]
+            )
+        cls.process = popen_launch_server(
+            cls.model,
+            cls.base_url,
+            timeout=DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
+            other_args=other_args,
+        )
+
+    @classmethod
+    def tearDownClass(cls):
+        kill_process_tree(cls.process.pid)
+
+    def test_gsm8k(self):
+        requests.get(self.base_url + "/flush_cache")
+
+        args = SimpleNamespace(
+            num_shots=5,
+            data_path=None,
+            num_questions=200,
+            max_new_tokens=512,
+            parallel=128,
+            host="http://127.0.0.1",
+            port=int(self.base_url.split(":")[-1]),
+        )
+        metrics = run_eval_few_shot_gsm8k(args)
+        print(metrics)
+
+        self.assertGreater(metrics["accuracy"], 0.60)
+
+        server_info = requests.get(self.base_url + "/get_server_info")
+        print(f"{server_info=}")
+        avg_spec_accept_length = server_info.json()["internal_states"][0][
+            "avg_spec_accept_length"
+        ]
+        print(f"{avg_spec_accept_length=}")
+        self.assertGreater(avg_spec_accept_length, 1.8)
+
+
 if __name__ == "__main__":
     unittest.main()