test: align moe alltoall combine coverage with model specs

Cover the combine path with parameter sets that mirror representative MoE model configurations and add focused Qwen coverage for dtype and workspace staging. This keeps the regression matrix closer to real-world routing shapes while preserving targeted edge-case checks.

Author: bobboli

tests/comm/test_trtllm_moe_alltoall.py

@@ -52,15 +52,22 @@ def setup_test_environment():
     (8, 16),  # 8 ranks
 ]
 
+# (world_size, num_tokens, vector_dim, top_k, dtype, payload_in_workspace)
 COMBINE_PARAMS = [
-    (2, 64, 8, 2, torch.bfloat16, True),  # Small input, 2 ranks
-    (4, 32, 32768, 4, torch.bfloat16, True),  # Large input, 4 ranks
-    (8, 16, 2048, 8, torch.bfloat16, True),  # Medium input, 8 ranks
-    (8, 16, 2048, 8, torch.bfloat16, False),  # Medium input, 8 ranks
-    (2, 64, 8, 2, torch.float16, True),  # Small input, 2 ranks
-    (4, 32, 32768, 4, torch.float16, True),  # Large input, 4 ranks
-    (8, 16, 2048, 8, torch.float16, True),  # Medium input, 8 ranks
-    (8, 16, 2048, 8, torch.float16, False),  # Medium input, 8 ranks
+    # Coverage for popular model specifications
+    (4, 16, 4096, 2, torch.bfloat16, True),     # Mixtral-8x7B
+    (4, 16, 2880, 4, torch.bfloat16, True),     # GPT-OSS-120B
+    (8, 16, 5120, 6, torch.bfloat16, True),     # DeepSeek-V2
+    (8, 16, 7168, 8, torch.bfloat16, True),     # DeepSeek-V3
+    (8, 16, 4096, 8, torch.bfloat16, True),     # Qwen3-235B-A22B
+    (8, 16, 4096, 10, torch.bfloat16, True),    # Qwen3.5-397B-A17B 
+    (8, 16, 4096, 22, torch.bfloat16, True),    # Nemotron-3-Super-120B-A12B
+    # Coverage for num_tokens
+    (8, 1, 4096, 8, torch.bfloat16, True),
+    # Coverage for dtype
+    (8, 16, 4096, 8, torch.float16, True),
+    # Coverage for payload_in_workspace
+    (8, 16, 4096, 8, torch.bfloat16, False),
 ]
 
 
@@ -465,7 +472,7 @@ def test_moe_combine_multi_rank_single_gpu(
 ):
     torch.cuda.set_device(0)
     check_sufficient_sm_count(num_tokens, world_size)
-    max_world_size = 8
+    max_world_size = 16
     assert world_size <= max_world_size, (
         f"should run with world_size at most {max_world_size}"
     )