diff --git a/llumnix/config/default.py b/llumnix/config/default.py
index 358d9e1b..c5fba7a8 100644
--- a/llumnix/config/default.py
+++ b/llumnix/config/default.py
@@ -112,7 +112,7 @@
 # Number of kv-cache layers to transfer in each round during migration
 _C.MANAGER.MIGRATION_NUM_LAYERS = 1
 # Number of internal cache size in migration backend for sending and receiving
-_C.MANAGER.MIGRATION_INTERNAL_BUFFER_NUM = 2
+_C.MANAGER.MIGRATION_INTERNAL_BUFFER_NUM = 1
 
 # -----------------------------------------------------------------------------
 # SCALING CONFIGURATION
diff --git a/tests/e2e_test/utils.py b/tests/e2e_test/utils.py
index 4783496d..146f6dfe 100644
--- a/tests/e2e_test/utils.py
+++ b/tests/e2e_test/utils.py
@@ -71,7 +71,7 @@ def generate_launch_command(result_filename: str = "",
         f"--request-migration-policy {request_migration_policy} "
         f"--migration-backend {migration_backend} "
         f"--migration-buffer-blocks 32 "
-        f"--migration-internal-buffer-num 2 "
+        f"--migration-internal-buffer-num 1 "
         f"--tensor-parallel-size 1 "
         f"--request-output-queue-port {1234+port} "
         f"{'--launch-ray-cluster ' if launch_ray_cluster else ''}"