Set max_cores and max_workers to None (#478)

* Set max_cores and max_workers to None

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* By default get the number of cores from the multiprocessing package

* Test Fixes

* more fixes

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

executorlib/__init__.py

@@ -83,10 +83,10 @@ class Executor:
 
     def __init__(
         self,
-        max_workers: int = 1,
+        max_workers: Optional[int] = None,
         backend: str = "local",
         cache_directory: Optional[str] = None,
-        max_cores: int = 1,
+        max_cores: Optional[int] = None,
         resource_dict: Optional[dict] = None,
         flux_executor=None,
         flux_executor_pmi_mode: Optional[str] = None,
@@ -104,10 +104,10 @@ def __init__(
 
     def __new__(
         cls,
-        max_workers: int = 1,
+        max_workers: Optional[int] = None,
         backend: str = "local",
         cache_directory: Optional[str] = None,
-        max_cores: int = 1,
+        max_cores: Optional[int] = None,
         resource_dict: Optional[dict] = None,
         flux_executor=None,
         flux_executor_pmi_mode: Optional[str] = None,

executorlib/interactive/executor.py

@@ -147,9 +147,9 @@ def __exit__(
 
 
 def create_executor(
-    max_workers: int = 1,
+    max_workers: Optional[int] = None,
     backend: str = "local",
-    max_cores: int = 1,
+    max_cores: Optional[int] = None,
     cache_directory: Optional[str] = None,
     resource_dict: Optional[dict] = None,
     flux_executor=None,

executorlib/standalone/inputcheck.py

@@ -1,4 +1,5 @@
 import inspect
+import multiprocessing
 from concurrent.futures import Executor
 from typing import Callable, List, Optional
 
@@ -131,12 +132,14 @@ def check_init_function(block_allocation: bool, init_function: Callable) -> None
         raise ValueError("")
 
 
-def check_max_workers_and_cores(max_workers: int, max_cores: int) -> None:
-    if max_workers != 1:
+def check_max_workers_and_cores(
+    max_workers: Optional[int], max_cores: Optional[int]
+) -> None:
+    if max_workers is not None:
         raise ValueError(
             "The number of workers cannot be controlled with the pysqa based backend."
         )
-    if max_cores != 1:
+    if max_cores is not None:
         raise ValueError(
             "The number of cores cannot be controlled with the pysqa based backend."
         )
@@ -166,10 +169,15 @@ def check_pysqa_config_directory(pysqa_config_directory: Optional[str]) -> None:
         )
 
 
-def validate_number_of_cores(max_cores: int, max_workers: int) -> int:
+def validate_number_of_cores(
+    max_cores: Optional[int], max_workers: Optional[int]
+) -> int:
     """
     Validate the number of cores and return the appropriate value.
     """
-    if max_workers != 1 and max_cores == 1:
+    if max_workers is None and max_cores is None:
+        return multiprocessing.cpu_count()
+    elif max_workers is not None and max_cores is None:
         return max_workers
-    return max_cores
+    else:
+        return max_cores

tests/test_integration_pyiron_workflow.py

@@ -74,7 +74,7 @@ def slowly_returns_dynamic(dynamic_arg):
             return dynamic_arg
 
         dynamic_dynamic = slowly_returns_dynamic()
-        executor = Executor(block_allocation=True)
+        executor = Executor(block_allocation=True, max_workers=1)
         cloudpickle_register(ind=1)
         dynamic_object = does_nothing()
         fs = executor.submit(dynamic_dynamic.run, dynamic_object)
@@ -104,7 +104,7 @@ def slowly_returns_42():
         self.assertIsNone(
             dynamic_42.result, msg="Just a sanity check that the test is set up right"
         )
-        executor = Executor(block_allocation=True)
+        executor = Executor(block_allocation=True, max_workers=1)
         cloudpickle_register(ind=1)
         fs = executor.submit(dynamic_42.run)
         fs.add_done_callback(dynamic_42.process_result)
@@ -135,7 +135,7 @@ def returns_42():
             dynamic_42.running,
             msg="Sanity check that the test starts in the expected condition",
         )
-        executor = Executor(block_allocation=True)
+        executor = Executor(block_allocation=True, max_workers=1)
         cloudpickle_register(ind=1)
         fs = executor.submit(dynamic_42.run)
         fs.add_done_callback(dynamic_42.process_result)
@@ -159,7 +159,7 @@ def raise_error():
             raise RuntimeError
 
         re = raise_error()
-        executor = Executor(block_allocation=True)
+        executor = Executor(block_allocation=True, max_workers=1)
         cloudpickle_register(ind=1)
         fs = executor.submit(re.run)
         with self.assertRaises(
@@ -189,7 +189,7 @@ def slowly_returns_dynamic():
             return inside_variable
 
         dynamic_dynamic = slowly_returns_dynamic()
-        executor = Executor(block_allocation=True)
+        executor = Executor(block_allocation=True, max_workers=1)
         cloudpickle_register(ind=1)
         fs = executor.submit(dynamic_dynamic.run)
         self.assertIsInstance(
@@ -218,7 +218,7 @@ def slow():
             return fortytwo
 
         f = slow()
-        executor = Executor(block_allocation=True)
+        executor = Executor(block_allocation=True, max_workers=1)
         cloudpickle_register(ind=1)
         fs = executor.submit(f.run)
         self.assertEqual(

tests/test_local_executor_future.py

@@ -68,6 +68,7 @@ def submit():
                 # Executor only exists in this scope and can get garbage collected after
                 # this function is exits
                 future = InteractiveExecutor(
+                    max_workers=1,
                     executor_kwargs={},
                     spawner=MpiExecSpawner,
                 ).submit(slow_callable)
@@ -108,6 +109,7 @@ def run(self):
                     self.running = True
 
                     future = InteractiveExecutor(
+                        max_workers=1,
                         executor_kwargs={},
                         spawner=MpiExecSpawner,
                     ).submit(self.return_42)

tests/test_shared_input_check.py

@@ -17,6 +17,7 @@
     check_max_workers_and_cores,
     check_hostname_localhost,
     check_pysqa_config_directory,
+    validate_number_of_cores,
 )
 
 
@@ -80,9 +81,9 @@ def test_check_flux_executor_pmi_mode(self):
 
     def test_check_max_workers_and_cores(self):
         with self.assertRaises(ValueError):
-            check_max_workers_and_cores(max_workers=2, max_cores=1)
+            check_max_workers_and_cores(max_workers=2, max_cores=None)
         with self.assertRaises(ValueError):
-            check_max_workers_and_cores(max_workers=1, max_cores=2)
+            check_max_workers_and_cores(max_workers=None, max_cores=2)
         with self.assertRaises(ValueError):
             check_max_workers_and_cores(max_workers=2, max_cores=2)
 
@@ -95,3 +96,14 @@ def test_check_hostname_localhost(self):
     def test_check_pysqa_config_directory(self):
         with self.assertRaises(ValueError):
             check_pysqa_config_directory(pysqa_config_directory="path/to/config")
+
+    def test_validate_number_of_cores(self):
+        self.assertIsInstance(
+            validate_number_of_cores(max_cores=None, max_workers=None), int
+        )
+        self.assertIsInstance(
+            validate_number_of_cores(max_cores=1, max_workers=None), int
+        )
+        self.assertIsInstance(
+            validate_number_of_cores(max_cores=None, max_workers=1), int
+        )

tests/test_shell_interactive.py

@@ -105,6 +105,7 @@ def test_execute_single_task(self):
     def test_shell_interactive_executor(self):
         cloudpickle_register(ind=1)
         with Executor(
+            max_workers=1,
             init_function=init_process,
             block_allocation=True,
         ) as exe: