Merge pull request #645 from Routstr/fix/increase-default-db-pool

fix(db): increase default connection pool capacity

.env.example

@@ -26,9 +26,9 @@ ROUTSTR_SECRET_KEY=
 # logged at startup. Keep total capacity across all workers below the database
 # connection limit. Pre-ping is automatic for networked backends; SQLite may
 # explicitly opt in if desired.
-# DATABASE_POOL_SIZE=5
-# DATABASE_MAX_OVERFLOW=10
-# DATABASE_POOL_TIMEOUT=30
+# DATABASE_POOL_SIZE=10
+# DATABASE_MAX_OVERFLOW=20
+# DATABASE_POOL_TIMEOUT=15
 # DATABASE_POOL_RECYCLE=1800
 # DATABASE_POOL_PRE_PING=false
 # Warn when a checkout is held this many seconds.

routstr/core/settings.py

@@ -106,14 +106,14 @@ class Settings(BaseSettings):
         default=900, gt=0, env="REFUND_SWEEP_CLAIM_TIMEOUT_SECONDS"
     )
 
-    # Database connection-pool controls (advanced). Capacity defaults match
-    # SQLAlchemy's established queue-pool behavior. Pre-ping is enabled by the
-    # engine factory for networked backends; SQLite can explicitly opt in.
-    # These fields are env-only below.
-    database_pool_size: int = Field(default=5, ge=1, env="DATABASE_POOL_SIZE")
-    database_max_overflow: int = Field(default=10, ge=0, env="DATABASE_MAX_OVERFLOW")
+    # Database connection-pool controls (advanced). Capacity defaults provide
+    # headroom for Routstr's concurrent request and background-payment workload.
+    # Pre-ping is enabled by the engine factory for networked backends; SQLite
+    # can explicitly opt in. These fields are env-only below.
+    database_pool_size: int = Field(default=10, ge=1, env="DATABASE_POOL_SIZE")
+    database_max_overflow: int = Field(default=20, ge=0, env="DATABASE_MAX_OVERFLOW")
     database_pool_timeout: float = Field(
-        default=30.0, gt=0, env="DATABASE_POOL_TIMEOUT"
+        default=15.0, gt=0, env="DATABASE_POOL_TIMEOUT"
     )
     database_pool_recycle: int = Field(default=1800, ge=0, env="DATABASE_POOL_RECYCLE")
     database_pool_pre_ping: bool = Field(default=False, env="DATABASE_POOL_PRE_PING")

tests/unit/test_settings.py

@@ -62,11 +62,11 @@ def test_payout_settings_have_sensible_defaults() -> None:
     assert s.payout_interval_seconds == 900
 
 
-def test_database_pool_defaults_match_sqlalchemy_capacity() -> None:
+def test_database_pool_defaults_provide_concurrency_headroom() -> None:
     s = Settings()
-    assert s.database_pool_size == 5
-    assert s.database_max_overflow == 10
-    assert s.database_pool_timeout == 30.0
+    assert s.database_pool_size == 10
+    assert s.database_max_overflow == 20
+    assert s.database_pool_timeout == 15.0
     assert s.database_pool_recycle == 1800
     assert s.database_pool_pre_ping is False
     assert s.database_pool_hold_warn_seconds == 10.0
@@ -139,7 +139,7 @@ async def test_update_does_not_apply_env_only_fields_to_live_settings(
     from the running pool.
     """
     monkeypatch.delenv("DATABASE_POOL_SIZE", raising=False)
-    monkeypatch.setattr(settings, "database_pool_size", 5)
+    monkeypatch.setattr(settings, "database_pool_size", 10)
 
     engine = create_async_engine("sqlite+aiosqlite:///:memory:")
     async with AsyncSession(engine, expire_on_commit=False) as session:
@@ -151,7 +151,7 @@ async def test_update_does_not_apply_env_only_fields_to_live_settings(
         # A non-env-only field still updates normally...
         assert settings.name == "PoolTweaker"
         # ...but the env-only pool size stays at the boot value.
-        assert settings.database_pool_size == 5
+        assert settings.database_pool_size == 10
         # ...and it is never written to the settings blob.
         blob = await _read_settings_blob(session)
         assert "database_pool_size" not in blob