[Piecewise Cuda Graph] rename, refactor and add more logging

python/sglang/srt/compilation/backend.py

@@ -20,6 +20,7 @@
 from sglang.srt.compilation.compiler_interface import EagerAdapter, InductorAdaptor
 from sglang.srt.compilation.cuda_piecewise_backend import CUDAPiecewiseBackend
 from sglang.srt.compilation.pass_manager import PostGradPassManager
+from sglang.srt.utils.common import rank0_log
 
 logger = logging.getLogger(__name__)
 
@@ -357,6 +358,7 @@ def __init__(
         config: CompilationConfig,
         graph_pool: Any,
     ):
+        rank0_log(f"Initializing SGLangBackend")
         assert graph_pool is not None
         self.graph_pool = graph_pool
 
@@ -375,6 +377,7 @@ def configure_post_pass(self):
         self.inductor_config["post_grad_custom_post_pass"] = self.post_grad_pass_manager
 
     def __call__(self, graph: fx.GraphModule, example_inputs) -> Callable:
+        rank0_log(f"SGLangBackend __call__")
         base_cache_dir = os.path.expanduser(
             os.getenv("SGLANG_CACHE_DIR", "~/.cache/sglang/")
         )
@@ -441,7 +444,7 @@ def __call__(self, graph: fx.GraphModule, example_inputs) -> Callable:
             with open(graph_path, "w") as f:
                 f.write(src)
 
-            logger.debug("Computation graph saved to %s", graph_path)
+            rank0_log(f"Computation graph saved to {graph_path}")
 
         self._called = True
         return self.split_gm

python/sglang/srt/compilation/compile.py

@@ -11,6 +11,7 @@
 import torch
 
 from sglang.srt.compilation.compilation_config import CompilationConfig
+from sglang.srt.utils.common import rank0_log
 
 logger = logging.getLogger(__name__)
 
@@ -129,6 +130,7 @@ def install_torch_compiled(
     fullgraph: bool = True,
     graph_pool: Any = None,
 ):
+    rank0_log(f"install_torch_compiled")
     unbound_fwd = module.__class__.forward
     if not callable(unbound_fwd):
         raise TypeError("module.__class__.forward must be callable")

python/sglang/srt/model_executor/piecewise_cuda_graph_runner.py

@@ -59,6 +59,27 @@
     from sglang.srt.model_executor.model_runner import ModelRunner
 
 
+@contextmanager
+def disable_ca_comm(tp_group):
+    """
+    Context manager to temporarily disable custom allreduce communication.
+
+    This is used during Piecewise CUDA graph capture to avoid custom allreduce operations
+    that may not be compatible with graph capture.
+
+    TODO(yuwei): Fix this
+    """
+    old_disabled = None
+    try:
+        if tp_group.ca_comm is not None:
+            old_disabled = tp_group.ca_comm.disabled
+            tp_group.ca_comm.disabled = True
+        yield
+    finally:
+        if tp_group.ca_comm is not None and old_disabled is not None:
+            tp_group.ca_comm.disabled = old_disabled
+
+
 @contextmanager
 def freeze_gc(enable_cudagraph_gc: bool):
     """
@@ -207,7 +228,7 @@ def __init__(self, model_runner: ModelRunner):
                 )
 
                 with set_compiled(True):
-                    self.warmup_and_capture()
+                    self.warmup_torch_compile()
 
                 # Capture
                 try:
@@ -219,7 +240,8 @@ def __init__(self, model_runner: ModelRunner):
 
         self.raw_num_tokens = 0
 
-    def warmup_and_capture(self):
+    def warmup_torch_compile(self):
+        """Warmup the model with a simple forward pass before CUDA graph capture."""
         num_tokens = 2
         with torch.device(self.device):
             forward_batch = ForwardBatch(
@@ -283,7 +305,7 @@ def warmup_and_capture(self):
 
         with set_forward_context(
             forward_batch, self.attention_layers, self.quant_config
-        ):
+        ), disable_ca_comm(self.model_runner.tp_group):
             _ = self.model_runner.model.forward(
                 forward_batch.input_ids,
                 forward_batch.positions,
@@ -311,10 +333,9 @@ def capture(self) -> None:
         # Trigger CUDA graph capture for specific shapes.
         # Capture the large shapes first so that the smaller shapes
         # can reuse the memory pool allocated for the large shapes.
-        with freeze_gc(self.model_runner.server_args.enable_cudagraph_gc):
-            if self.model_runner.tp_group.ca_comm is not None:
-                old_ca_disable = self.model_runner.tp_group.ca_comm.disabled
-                self.model_runner.tp_group.ca_comm.disabled = True
+        with freeze_gc(
+            self.model_runner.server_args.enable_cudagraph_gc
+        ), disable_ca_comm(self.model_runner.tp_group):
             avail_mem = get_available_gpu_memory(
                 self.model_runner.device,
                 self.model_runner.gpu_id,
@@ -342,8 +363,6 @@ def capture(self) -> None:
 
                 # Save gemlite cache after each capture
                 save_gemlite_cache()
-            if self.model_runner.tp_group.ca_comm is not None:
-                self.model_runner.tp_group.ca_comm.disabled = old_ca_disable
 
     def capture_one_batch_size(self, num_tokens: int):
         bs = 1
@@ -565,10 +584,7 @@ def replay(
         forward_batch: ForwardBatch,
         **kwargs,
     ) -> Union[LogitsProcessorOutput, PPProxyTensors]:
-        with enable_piecewise_cuda_graph():
-            if self.model_runner.tp_group.ca_comm is not None:
-                old_ca_disable = self.model_runner.tp_group.ca_comm.disabled
-                self.model_runner.tp_group.ca_comm.disabled = True
+        with enable_piecewise_cuda_graph(), disable_ca_comm(self.model_runner.tp_group):
             self.model_runner.attn_backend.init_forward_metadata(forward_batch)
             static_forward_batch = self.replay_prepare(forward_batch, **kwargs)
             # Replay
@@ -599,8 +615,6 @@ def replay(
                     raise NotImplementedError(
                         "PPProxyTensors is not supported in PiecewiseCudaGraphRunner yet."
                     )
-            if self.model_runner.tp_group.ca_comm is not None:
-                self.model_runner.tp_group.ca_comm.disabled = old_ca_disable
 
     def get_spec_info(self, num_tokens: int):
         spec_info = None

python/sglang/srt/tokenizer/tiktoken_tokenizer.py

@@ -127,6 +127,7 @@ def apply_chat_template(
         add_generation_prompt,
         tools=None,
         reasoning_effort=None,
+        **kwargs,  # Accept additional parameters (e.g., return_dict) for compatibility
     ):
         ret = self.chat_template_jinja.render(
             messages=messages, add_generation_prompt=add_generation_prompt