Add FP8 Blockwise GEMM Backend Flag --fp8-gemm-backend (#14379)

test/srt/run_suite.py

@@ -170,6 +170,7 @@ suites = {
     "per-commit-4-gpu-b200": [
         TestFile("test_deepseek_v3_fp4_4gpu.py", 1800),
         TestFile("test_flash_attention_4.py", 300),
+        TestFile("test_fp8_blockwise_gemm.py", 280),
         TestFile("test_gpt_oss_4gpu.py", 600),
         TestFile("test_llama31_fp4.py", 300),
         TestFile("test_eagle_infer_beta_dp_attention.py", 300),

test/srt/test_fp8_blockwise_gemm.py

@@ -0,0 +1,73 @@
+import unittest
+from types import SimpleNamespace
+from urllib.parse import urlparse
+
+from sglang.srt.utils import get_device_sm, kill_process_tree
+from sglang.test.few_shot_gsm8k import run_eval as run_eval_few_shot_gsm8k
+from sglang.test.test_utils import (
+    DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
+    DEFAULT_URL_FOR_TEST,
+    popen_launch_server,
+    try_cached_model,
+)
+
+MODEL_PATH = "Qwen/Qwen3-4B-Instruct-2507-FP8"
+
+
+class FP8BlockwiseGemmBase:
+    backend = None
+
+    @classmethod
+    def setUpClass(cls):
+        if cls.backend is None:
+            raise NotImplementedError("Subclass must set 'backend' attribute")
+        cls.model = try_cached_model(MODEL_PATH)
+        cls.base_url = DEFAULT_URL_FOR_TEST
+        other_args = [
+            "--trust-remote-code",
+            "--fp8-gemm-backend",
+            cls.backend,
+        ]
+        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):
+        parsed_url = urlparse(self.base_url)
+        args = SimpleNamespace(
+            num_shots=8,
+            data_path=None,
+            num_questions=1319,
+            max_new_tokens=512,
+            parallel=200,
+            host=f"{parsed_url.scheme}://{parsed_url.hostname}",
+            port=parsed_url.port,
+        )
+        metrics = run_eval_few_shot_gsm8k(args)
+        print(metrics)
+
+        self.assertGreaterEqual(metrics["accuracy"], 0.41)
+
+
+class TestFP8BlockwiseGemmTriton(FP8BlockwiseGemmBase, unittest.TestCase):
+    backend = "triton"
+
+
+class TestFP8BlockwiseGemmDeepGemm(FP8BlockwiseGemmBase, unittest.TestCase):
+    backend = "deep_gemm"
+
+
+@unittest.skipIf(get_device_sm() < 100, "Test requires CUDA SM 100 or higher")
+class TestFP8BlockwiseGemmFlashinferTrtllm(FP8BlockwiseGemmBase, unittest.TestCase):
+    backend = "flashinfer_trtllm"
+
+
+if __name__ == "__main__":
+    unittest.main()