[Core][Serve] Hide execute api from sky.execution (#3058)

* change to launch

* move constants back

sky/backends/backend_utils.py

@@ -32,6 +32,7 @@
 from sky import exceptions
 from sky import global_user_state
 from sky import provision as provision_lib
+from sky import serve as serve_lib
 from sky import sky_logging
 from sky import skypilot_config
 from sky import status_lib
@@ -2525,7 +2526,7 @@ def get_task_demands_dict(task: 'task_lib.Task') -> Dict[str, float]:
     # For sky serve controller task, we set the CPU resource to a smaller
     # value to support a larger number of services.
     resources_dict = {
-        'CPU': (constants.SERVICES_TASK_CPU_DEMAND
+        'CPU': (serve_lib.SERVICES_TASK_CPU_DEMAND
                 if task.service_name is not None else DEFAULT_TASK_CPU_DEMAND)
     }
     if task.best_resources is not None:
@@ -2546,7 +2547,7 @@ def get_task_resources_str(task: 'task_lib.Task') -> str:
     The resources string is only used as a display purpose, so we only show
     the accelerator demands (if any). Otherwise, the CPU demand is shown.
     """
-    task_cpu_demand = (constants.SERVICES_TASK_CPU_DEMAND if task.service_name
+    task_cpu_demand = (serve_lib.SERVICES_TASK_CPU_DEMAND if task.service_name
                        is not None else DEFAULT_TASK_CPU_DEMAND)
     if task.best_resources is not None:
         accelerator_dict = task.best_resources.accelerators

sky/execution.py

@@ -143,7 +143,7 @@ def _maybe_clone_disk_from_cluster(clone_disk_from: Optional[str],
     return task
 
 
-def execute(
+def _execute(
     entrypoint: Union['sky.Task', 'sky.Dag'],
     dryrun: bool = False,
     down: bool = False,
@@ -402,6 +402,7 @@ def launch(
     # pylint: disable=invalid-name
     _is_launched_by_spot_controller: bool = False,
     _is_launched_by_sky_serve_controller: bool = False,
+    _disable_controller_check: bool = False,
 ) -> Tuple[Optional[int], Optional[backends.ResourceHandle]]:
     # NOTE(dev): Keep the docstring consistent between the Python API and CLI.
     """Launch a cluster or task.
@@ -490,10 +491,11 @@ def launch(
         if dryrun.
     """
     entrypoint = task
-    controller_utils.check_cluster_name_not_controller(
-        cluster_name, operation_str='sky.launch')
+    if not _disable_controller_check:
+        controller_utils.check_cluster_name_not_controller(
+            cluster_name, operation_str='sky.launch')
 
-    return execute(
+    return _execute(
         entrypoint=entrypoint,
         dryrun=dryrun,
         down=down,
@@ -590,7 +592,7 @@ def exec(  # pylint: disable=redefined-builtin
         operation='executing tasks',
         check_cloud_vm_ray_backend=False,
         dryrun=dryrun)
-    return execute(
+    return _execute(
         entrypoint=entrypoint,
         dryrun=dryrun,
         down=down,
@@ -701,7 +703,7 @@ def spot_launch(
               f'Launching managed spot job {dag.name!r} from spot controller...'
               f'{colorama.Style.RESET_ALL}')
         print('Launching spot controller...')
-        execute(
+        _execute(
             entrypoint=controller_task,
             stream_logs=stream_logs,
             cluster_name=controller_name,

sky/serve/__init__.py

@@ -4,6 +4,7 @@
 from sky.serve.constants import ENDPOINT_PROBE_INTERVAL_SECONDS
 from sky.serve.constants import INITIAL_VERSION
 from sky.serve.constants import LB_CONTROLLER_SYNC_INTERVAL_SECONDS
+from sky.serve.constants import SERVICES_TASK_CPU_DEMAND
 from sky.serve.constants import SKYSERVE_METADATA_DIR
 from sky.serve.core import down
 from sky.serve.core import status

sky/serve/constants.py

@@ -53,6 +53,10 @@
 # do some log rotation.
 CONTROLLER_RESOURCES = {'cpus': '4+', 'disk_size': 200}
 
+# A default controller with 4 vCPU and 16 GB memory can run up to 16 services.
+SERVICES_MEMORY_USAGE_GB = 1.0
+SERVICES_TASK_CPU_DEMAND = 0.25
+
 # A period of time to initialize your service. Any readiness probe failures
 # during this period will be ignored.
 DEFAULT_INITIAL_DELAY_SECONDS = 1200

sky/serve/core.py

@@ -42,10 +42,6 @@ def up(
         task: sky.Task to serve up.
         service_name: Name of the service.
     """
-    # This is to avoid circular import.
-    # pylint: disable=import-outside-toplevel
-    from sky import execution
-
     if service_name is None:
         service_name = serve_utils.generate_service_name()
 
@@ -163,14 +159,15 @@ def up(
         # whether the service is already running. If the id is the same
         # with the current job id, we know the service is up and running
         # for the first time; otherwise it is a name conflict.
-        controller_job_id, controller_handle = execution.execute(
-            entrypoint=controller_task,
+        controller_job_id, controller_handle = sky.launch(
+            task=controller_task,
             stream_logs=False,
             cluster_name=controller_name,
             detach_run=True,
             idle_minutes_to_autostop=constants.
             CONTROLLER_IDLE_MINUTES_TO_AUTOSTOP,
             retry_until_up=True,
+            _disable_controller_check=True,
         )
 
         style = colorama.Style

sky/serve/serve_utils.py

@@ -25,7 +25,6 @@
 from sky import status_lib
 from sky.serve import constants
 from sky.serve import serve_state
-from sky.skylet import constants as skylet_constants
 from sky.skylet import job_lib
 from sky.utils import common_utils
 from sky.utils import log_utils
@@ -38,8 +37,7 @@
 SKY_SERVE_CONTROLLER_NAME: str = (
     f'sky-serve-controller-{common_utils.get_user_hash()}')
 _SYSTEM_MEMORY_GB = psutil.virtual_memory().total // (1024**3)
-NUM_SERVICE_THRESHOLD = (_SYSTEM_MEMORY_GB //
-                         skylet_constants.SERVICES_MEMORY_USAGE_GB)
+NUM_SERVICE_THRESHOLD = _SYSTEM_MEMORY_GB // constants.SERVICES_MEMORY_USAGE_GB
 _CONTROLLER_URL = 'http://localhost:{CONTROLLER_PORT}'
 
 _SKYPILOT_PROVISION_LOG_PATTERN = r'.*tail -n100 -f (.*provision\.log).*'

sky/skylet/constants.py

@@ -54,12 +54,6 @@
 # Port on the remote spot controller that the dashboard is running on.
 SPOT_DASHBOARD_REMOTE_PORT = 5000
 
-# A default controller with 4 vCPU and 16 GB memory can run up to 16 services.
-# TODO(tian): This is to fix circular imports. Move this back to
-# sky.serve.constants.
-SERVICES_MEMORY_USAGE_GB = 1.0
-SERVICES_TASK_CPU_DEMAND = 0.25
-
 # Docker default options
 DEFAULT_DOCKER_CONTAINER_NAME = 'sky_container'
 DEFAULT_DOCKER_PORT = 10022