perf: Improved parameters for working with the database

Author: iRingil

backend/src/app/core/db.py

@@ -21,7 +21,15 @@ def __init__(self, settings: Settings) -> None:
 
         :param settings: The application settings object.
         """
-        self._async_engine: AsyncEngine = create_async_engine(url=settings.sqlalchemy_database_uri)
+        self._async_engine: AsyncEngine = create_async_engine(
+            url=settings.sqlalchemy_database_uri,
+            # --- Recommendations for GENERAL DB (quota ~45 out of 100) ---
+            pool_size=3,  # Number of 'persistent' connections per worker.
+            max_overflow=2,  # Number of 'additional' connections for peaks.
+            pool_pre_ping=True,  # Check the connection before use.
+            pool_recycle=1700,  # Recreating 'old' connections.
+            pool_timeout=30,  # Waiting time for a free connection. (30 seconds)
+        )
         self._async_session_factory: async_sessionmaker[AsyncSession] = async_sessionmaker(
             bind=self._async_engine, class_=AsyncSession, expire_on_commit=False
         )

backend/tests/app/core/test_db.py

@@ -3,6 +3,7 @@
 
 # pylint: disable=protected-access
 # pylint: disable=redefined-outer-name
+# pylint: disable=duplicate-code
 
 from typing import Any
 from unittest.mock import AsyncMock
@@ -89,7 +90,14 @@ async def test_database_manager_init(
     db_manager: DatabaseManager = DatabaseManager(settings=mock_settings)
     assert db_manager._async_engine == mock_async_engine
     assert db_manager._async_session_factory == mock_async_session_factory
-    mock_create_async_engine.assert_called_once_with(url=mock_settings.sqlalchemy_database_uri)
+    mock_create_async_engine.assert_called_once_with(
+        url=mock_settings.sqlalchemy_database_uri,
+        pool_size=3,
+        max_overflow=2,
+        pool_pre_ping=True,
+        pool_recycle=1700,
+        pool_timeout=30,
+    )
     mock_async_sessionmaker.assert_called_once_with(bind=mock_async_engine, class_=AsyncSession, expire_on_commit=False)