new write_config to only update instead of completely overwrite config

Author: renxida

app_tests/benchmark_tests/llm/sglang_benchmarks/conftest.py

@@ -64,17 +64,39 @@ def pre_process_model(request, tmp_path_factory):
 
 
 @pytest.fixture(scope="module")
-def write_config(request, pre_process_model):
+def write_config(request, model_test_dir):
     batch_sizes = request.param["batch_sizes"]
     prefix_sharing_algorithm = request.param["prefix_sharing_algorithm"]
 
-    logger.info("Writing config file..." + start_log_group("Writing config file"))
-
+    # Construct the new config filename
     config_path = (
-        pre_process_model
+        model_test_dir
         / f"{'_'.join(str(bs) for bs in batch_sizes)}_{prefix_sharing_algorithm}.json"
     )
 
+    # Read the base config file
+    base_config_path = model_test_dir / "config.json"
+    with open(base_config_path, "r") as f:
+        config = json.load(f)
+
+    # Override specific fields
+    config.update(
+        {
+            "prefill_batch_sizes": batch_sizes,
+            "decode_batch_sizes": batch_sizes,
+            "paged_kv_cache": {
+                **config.get(
+                    "paged_kv_cache", {}
+                ),  # Preserve other paged_kv_cache settings
+                "prefix_sharing_algorithm": prefix_sharing_algorithm,
+            },
+        }
+    )
+
+    logger.info(f"Saving edited config to: {config_path}\n")
+    logger.info(f"Config: {json.dumps(config, indent=2)}")
+    with open(config_path, "w") as f:
+        json.dump(config, f)
     yield config_path
 
 

app_tests/integration_tests/llm/shortfin/conftest.py

@@ -87,10 +87,35 @@ def write_config(request, model_test_dir):
     batch_sizes = request.param["batch_sizes"]
     prefix_sharing_algorithm = request.param["prefix_sharing_algorithm"]
 
+    # Construct the new config filename
     config_path = (
         model_test_dir
         / f"{'_'.join(str(bs) for bs in batch_sizes)}_{prefix_sharing_algorithm}.json"
     )
+
+    # Read the base config file
+    base_config_path = model_test_dir / "config.json"
+    with open(base_config_path, "r") as f:
+        config = json.load(f)
+
+    # Override specific fields
+    config.update(
+        {
+            "prefill_batch_sizes": batch_sizes,
+            "decode_batch_sizes": batch_sizes,
+            "paged_kv_cache": {
+                **config.get(
+                    "paged_kv_cache", {}
+                ),  # Preserve other paged_kv_cache settings
+                "prefix_sharing_algorithm": prefix_sharing_algorithm,
+            },
+        }
+    )
+    logger.info(f"Saving edited config to: {config_path}\n")
+    logger.info(f"Config: {json.dumps(config, indent=2)}")
+    with open(config_path, "w") as f:
+        json.dump(config, f)
+
     yield config_path