[misc] fix: set default value of ETP to 1 (#3371)

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Author: vermouth1992

tests/special_e2e/run_ppo_trainer_megatron.sh

@@ -58,7 +58,7 @@ COMMON_VPP=${COMMON_VPP:-2}
 COMMON_CP=${COMMON_CP:-2}
 COMMON_TP=${COMMON_TP:-2}
 COMMON_EP=${COMMON_EP:-1}
-COMMON_ETP=${COMMON_ETP:-null}
+COMMON_ETP=${COMMON_ETP:-1}
 
 TRAIN_TP=${TRAIN_TP:-$COMMON_TP}
 INFER_TP=${INFER_TP:-$COMMON_TP}

verl/trainer/config/_generated_ppo_megatron_trainer.yaml

@@ -33,7 +33,7 @@ actor_rollout_ref:
       optimizer_offload: false
       tensor_model_parallel_size: 1
       expert_model_parallel_size: 1
-      expert_tensor_parallel_size: null
+      expert_tensor_parallel_size: 1
       pipeline_model_parallel_size: 1
       virtual_pipeline_model_parallel_size: null
       context_parallel_size: 1
@@ -155,7 +155,7 @@ actor_rollout_ref:
       optimizer_offload: false
       tensor_model_parallel_size: 1
       expert_model_parallel_size: 1
-      expert_tensor_parallel_size: null
+      expert_tensor_parallel_size: 1
       pipeline_model_parallel_size: 1
       virtual_pipeline_model_parallel_size: null
       context_parallel_size: 1
@@ -325,7 +325,7 @@ critic:
     optimizer_offload: false
     tensor_model_parallel_size: 1
     expert_model_parallel_size: 1
-    expert_tensor_parallel_size: null
+    expert_tensor_parallel_size: 1
     pipeline_model_parallel_size: 1
     virtual_pipeline_model_parallel_size: null
     context_parallel_size: 1

verl/trainer/config/engine/megatron.yaml

@@ -17,7 +17,7 @@ tensor_model_parallel_size: 1
 expert_model_parallel_size: 1
 
 # expert tensor parallel size
-expert_tensor_parallel_size: null
+expert_tensor_parallel_size: 1
 
 # pipeline model parallel size
 pipeline_model_parallel_size: 1