Clean logs for DeepSeek-V3 launching (#6079)

python/sglang/srt/distributed/device_communicators/pynccl.py

@@ -75,7 +75,8 @@ class PyNcclCommunicator:
         self.available = True
         self.disabled = False
 
-        logger.info("sglang is using nccl==%s", self.nccl.ncclGetVersion())
+        if self.rank == 0:
+            logger.info("sglang is using nccl==%s", self.nccl.ncclGetVersion())
 
         if self.rank == 0:
             # get the unique id from NCCL

python/sglang/srt/layers/moe/fused_moe_triton/fused_moe.py

@@ -29,6 +29,7 @@ from sglang.srt.utils import (
     get_device_name,
     is_cuda,
     is_hip,
+    log_info_on_rank0,
 )
 
 _is_hip = is_hip()
@@ -945,7 +946,9 @@ def get_moe_configs(
             # For example, updating the Triton version might cause all old configs to become suboptimal.
             # To achieve the best performance, consider re-tuning the Triton fused MOE kernel in your environment.
             # For the tuning method, refer to: https://github.com/sgl-project/sglang/tree/main/benchmark/kernels/fused_moe_triton
-            logger.info("Using MoE kernel config from %s.", config_file_path)
+            log_info_on_rank0(
+                logger, f"Using MoE kernel config from {config_file_path}."
+            )
             # If a configuration has been found, return it
             return {int(key): val for key, val in json.load(f).items()}
 

python/sglang/srt/layers/quantization/fp8.py

@@ -66,6 +66,7 @@ from sglang.srt.utils import (
     get_bool_env_var,
     is_cuda,
     is_hip,
+    log_info_on_rank0,
     print_warning_once,
     set_weight_attrs,
 )
@@ -104,10 +105,7 @@ class Fp8Config(QuantizationConfig):
     ) -> None:
         self.is_checkpoint_fp8_serialized = is_checkpoint_fp8_serialized
         if is_checkpoint_fp8_serialized:
-            logger.warning(
-                "Detected fp8 checkpoint. Please note that the "
-                "format is experimental and subject to change."
-            )
+            log_info_on_rank0(logger, "Detected fp8 checkpoint.")
         if activation_scheme not in ACTIVATION_SCHEMES:
             raise ValueError(f"Unsupported activation scheme {activation_scheme}")
         self.activation_scheme = activation_scheme

python/sglang/srt/layers/quantization/fp8_kernel.py

@@ -30,6 +30,7 @@ from sglang.srt.utils import (
     get_device_name,
     is_cuda,
     is_hip,
+    log_info_on_rank0,
     supports_custom_op,
 )
 
@@ -698,9 +699,9 @@ def get_w8a8_block_fp8_configs(
     )
     if os.path.exists(config_file_path):
         with open(config_file_path) as f:
-            logger.info(
-                "Using configuration from %s for W8A8 Block FP8 kernel.",
-                config_file_path,
+            log_info_on_rank0(
+                logger,
+                f"Using configuration from {config_file_path} for W8A8 Block FP8 kernel.",
             )
             # If a configuration has been found, return it
             return {int(key): val for key, val in json.load(f).items()}

python/sglang/srt/model_executor/model_runner.py

@@ -278,9 +278,10 @@ class ModelRunner:
                     server_args.attention_backend = "fa3"
                 else:
                     server_args.attention_backend = "triton"
-            logger.info(
-                f"Attention backend not set. Use {server_args.attention_backend} backend by default."
-            )
+            if self.should_log:
+                logger.info(
+                    f"Attention backend not set. Use {server_args.attention_backend} backend by default."
+                )
         elif self.use_mla_backend:
             if server_args.device != "cpu":
                 if server_args.attention_backend in [
@@ -290,9 +291,10 @@ class ModelRunner:
                     "flashmla",
                     "cutlass_mla",
                 ]:
-                    logger.info(
-                        f"MLA optimization is turned on. Use {server_args.attention_backend} backend."
-                    )
+                    if self.should_log:
+                        logger.info(
+                            f"MLA optimization is turned on. Use {server_args.attention_backend} backend."
+                        )
                 else:
                     raise ValueError(
                         f"Invalid attention backend for MLA: {server_args.attention_backend}"
@@ -311,9 +313,10 @@ class ModelRunner:
             server_args.attention_backend = "triton"
 
         if server_args.enable_double_sparsity:
-            logger.info(
-                "Double sparsity optimization is turned on. Use triton backend without CUDA graph."
-            )
+            if self.should_log:
+                logger.info(
+                    "Double sparsity optimization is turned on. Use triton backend without CUDA graph."
+                )
             server_args.attention_backend = "triton"
             server_args.disable_cuda_graph = True
             if server_args.ds_heavy_channel_type is None:
@@ -324,23 +327,26 @@ class ModelRunner:
 
         if self.is_multimodal:
             self.mem_fraction_static *= 0.90
-            logger.info(
-                f"Automatically reduce --mem-fraction-static to {self.mem_fraction_static:.3f} "
-                f"because this is a multimodal model."
-            )
-            logger.info(
-                "Automatically turn off --chunked-prefill-size for multimodal model."
-            )
+            if self.should_log:
+                logger.info(
+                    f"Automatically reduce --mem-fraction-static to {self.mem_fraction_static:.3f} "
+                    f"because this is a multimodal model."
+                )
+                logger.info(
+                    "Automatically turn off --chunked-prefill-size for multimodal model."
+                )
             server_args.chunked_prefill_size = -1
 
         if not self.use_mla_backend:
             server_args.disable_chunked_prefix_cache = True
         elif self.page_size > 1:
-            logger.info("Disable chunked prefix cache when page size > 1.")
+            if self.should_log:
+                logger.info("Disable chunked prefix cache when page size > 1.")
             server_args.disable_chunked_prefix_cache = True
 
         if not server_args.disable_chunked_prefix_cache:
-            logger.info("Chunked prefix cache is turned on.")
+            if self.should_log:
+                logger.info("Chunked prefix cache is turned on.")
 
     def init_torch_distributed(self):
         logger.info("Init torch distributed begin.")
@@ -433,9 +439,10 @@ class ModelRunner:
             torch.set_num_threads(1)
         if self.device == "cuda":
             if torch.cuda.get_device_capability()[0] < 8:
-                logger.info(
-                    "Compute capability below sm80. Use float16 due to lack of bfloat16 support."
-                )
+                if self.should_log:
+                    logger.info(
+                        "Compute capability below sm80. Use float16 due to lack of bfloat16 support."
+                    )
                 self.server_args.dtype = "float16"
                 self.model_config.dtype = torch.float16
                 if torch.cuda.get_device_capability()[1] < 5:
@@ -471,10 +478,11 @@ class ModelRunner:
                     self.model.load_kv_cache_scales(
                         self.server_args.quantization_param_path
                     )
-                    logger.info(
-                        "Loaded KV cache scaling factors from %s",
-                        self.server_args.quantization_param_path,
-                    )
+                    if self.should_log:
+                        logger.info(
+                            "Loaded KV cache scaling factors from %s",
+                            self.server_args.quantization_param_path,
+                        )
                 else:
                     raise RuntimeError(
                         "Using FP8 KV cache and scaling factors provided but "
@@ -1021,7 +1029,8 @@ class ModelRunner:
         )
 
     def apply_torch_tp(self):
-        logger.info(f"Enabling torch tensor parallelism on {self.tp_size} devices.")
+        if self.should_log:
+            logger.info(f"Enabling torch tensor parallelism on {self.tp_size} devices.")
         from sglang.srt.model_parallel import tensor_parallel
 
         device_mesh = torch.distributed.init_device_mesh(self.device, (self.tp_size,))

python/sglang/srt/models/deepseek_v2.py

@@ -88,6 +88,7 @@ from sglang.srt.utils import (
     get_int_env_var,
     is_cuda,
     is_hip,
+    log_info_on_rank0,
 )
 
 _is_hip = is_hip()
@@ -1485,8 +1486,9 @@ class DeepseekV2ForCausalLM(nn.Module):
             ):
                 self.n_share_experts_fusion = 0
                 global_server_args_dict["n_share_experts_fusion"] = 0
-                logger.info(
-                    "Only Deepseek V3/R1 can use shared experts fusion optimization. Shared experts fusion optimization is disabled."
+                log_info_on_rank0(
+                    logger,
+                    "Only Deepseek V3/R1 can use shared experts fusion optimization. Shared experts fusion optimization is disabled.",
                 )
             else:
                 assert (
@@ -1501,8 +1503,9 @@ class DeepseekV2ForCausalLM(nn.Module):
             ):
                 self.n_share_experts_fusion = self.tp_size
                 global_server_args_dict["n_share_experts_fusion"] = self.tp_size
-                logger.info(
-                    "Deepseek V3/R1 with fp8 can use shared experts fusion optimization when SM version >=90. Shared experts fusion optimization is enabled."
+                log_info_on_rank0(
+                    logger,
+                    "Deepseek V3/R1 with fp8 can use shared experts fusion optimization when SM version >=90. Shared experts fusion optimization is enabled.",
                 )
 
     def get_input_embeddings(self) -> nn.Embedding:

python/sglang/srt/utils.py

@@ -2096,3 +2096,10 @@ class BumpAllocator:
         output = self._buffer[self._pointer : self._pointer + size]
         self._pointer += size
         return output
+
+
+def log_info_on_rank0(logger, msg):
+    from sglang.srt.distributed import get_tensor_model_parallel_rank
+
+    if get_tensor_model_parallel_rank() == 0:
+        logger.info(msg)