Use our own executor

Author: NoahStapp

pymongo/__init__.py

@@ -15,6 +15,7 @@
 """Python driver for MongoDB."""
 from __future__ import annotations
 
+from concurrent.futures import ThreadPoolExecutor
 from typing import ContextManager, Optional
 
 __all__ = [
@@ -166,3 +167,6 @@ def timeout(seconds: Optional[float]) -> ContextManager[None]:
     if seconds is not None:
         seconds = float(seconds)
     return _csot._TimeoutContext(seconds)
+
+
+_PYMONGO_EXECUTOR = ThreadPoolExecutor(thread_name_prefix="PYMONGO_EXECUTOR-")

pymongo/asynchronous/pool.py

@@ -38,7 +38,7 @@
 )
 
 from bson import DEFAULT_CODEC_OPTIONS
-from pymongo import _csot, helpers_shared
+from pymongo import _PYMONGO_EXECUTOR, _csot, helpers_shared
 from pymongo.asynchronous.client_session import _validate_session_write_concern
 from pymongo.asynchronous.helpers import _handle_reauth
 from pymongo.asynchronous.network import command, receive_message
@@ -890,7 +890,7 @@ async def _configured_socket(
                 else:
                     loop = asyncio.get_running_loop()
                     ssl_sock = await loop.run_in_executor(
-                        None,
+                        _PYMONGO_EXECUTOR,
                         functools.partial(ssl_context.wrap_socket, sock, server_hostname=host),  # type: ignore[assignment, misc]
                     )
         else:
@@ -901,7 +901,9 @@ async def _configured_socket(
                     ssl_sock = await ssl_context.a_wrap_socket(sock)  # type: ignore[assignment, misc]
                 else:
                     loop = asyncio.get_running_loop()
-                    ssl_sock = await loop.run_in_executor(None, ssl_context.wrap_socket, sock)  # type: ignore[assignment, misc]
+                    ssl_sock = await loop.run_in_executor(
+                        _PYMONGO_EXECUTOR, ssl_context.wrap_socket, sock
+                    )  # type: ignore[assignment, misc]
     except _CertificateError:
         sock.close()
         # Raise _CertificateError directly like we do after match_hostname

pymongo/pyopenssl_context.py

@@ -31,6 +31,7 @@
 from OpenSSL import SSL as _SSL
 from OpenSSL import crypto as _crypto
 
+from pymongo import _PYMONGO_EXECUTOR
 from pymongo.errors import ConfigurationError as _ConfigurationError
 from pymongo.errors import _CertificateError  # type:ignore[attr-defined]
 from pymongo.ocsp_cache import _OCSPCache
@@ -405,15 +406,15 @@ async def a_wrap_socket(
                 ssl_conn.set_tlsext_host_name(server_hostname.encode("idna"))
             if self.verify_mode != _stdlibssl.CERT_NONE:
                 # Request a stapled OCSP response.
-                await loop.run_in_executor(None, ssl_conn.request_ocsp)
+                await loop.run_in_executor(_PYMONGO_EXECUTOR, ssl_conn.request_ocsp)
             ssl_conn.set_connect_state()
         # If this wasn't true the caller of wrap_socket would call
         # do_handshake()
         if do_handshake_on_connect:
             # XXX: If we do hostname checking in a callback we can get rid
             # of this call to do_handshake() since the handshake
             # will happen automatically later.
-            await loop.run_in_executor(None, ssl_conn.do_handshake)
+            await loop.run_in_executor(_PYMONGO_EXECUTOR, ssl_conn.do_handshake)
             # XXX: Do this in a callback registered with
             # SSLContext.set_info_callback? See Twisted for an example.
             if self.check_hostname and server_hostname is not None:

pymongo/synchronous/pool.py

@@ -38,7 +38,7 @@
 )
 
 from bson import DEFAULT_CODEC_OPTIONS
-from pymongo import _csot, helpers_shared
+from pymongo import _PYMONGO_EXECUTOR, _csot, helpers_shared
 from pymongo.common import (
     MAX_BSON_SIZE,
     MAX_MESSAGE_SIZE,
@@ -886,7 +886,7 @@ def _configured_socket(address: _Address, options: PoolOptions) -> Union[socket.
                 else:
                     loop = asyncio.get_running_loop()
                     ssl_sock = loop.run_in_executor(
-                        None,
+                        _PYMONGO_EXECUTOR,
                         functools.partial(ssl_context.wrap_socket, sock, server_hostname=host),  # type: ignore[assignment, misc]
                     )
         else:
@@ -897,7 +897,9 @@ def _configured_socket(address: _Address, options: PoolOptions) -> Union[socket.
                     ssl_sock = ssl_context.a_wrap_socket(sock)  # type: ignore[assignment, misc]
                 else:
                     loop = asyncio.get_running_loop()
-                    ssl_sock = loop.run_in_executor(None, ssl_context.wrap_socket, sock)  # type: ignore[assignment, misc]
+                    ssl_sock = loop.run_in_executor(
+                        _PYMONGO_EXECUTOR, ssl_context.wrap_socket, sock
+                    )  # type: ignore[assignment, misc]
     except _CertificateError:
         sock.close()
         # Raise _CertificateError directly like we do after match_hostname