Fix async engine missing pool_recycle and pool_pre_ping configuration#65276
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kaxil wants to merge 1 commit intoapache:mainfrom
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Fix async engine missing pool_recycle and pool_pre_ping configuration#65276kaxil wants to merge 1 commit intoapache:mainfrom
pool_recycle and pool_pre_ping configuration#65276kaxil wants to merge 1 commit intoapache:mainfrom
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The async SQLAlchemy engine was created without any pool health settings while the sync engine got pool_size, pool_recycle, pool_pre_ping, and max_overflow from [database] config. This meant dead connections from PostgreSQL idle timeouts or pgbouncer disconnects were never detected by the async pool. Read the same [database] config values for the async engine. Also respect SQL_ALCHEMY_POOL_ENABLED=False by using NullPool, matching the sync engine behavior.
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The async SQLAlchemy engine was created with zero pool configuration while the sync engine got pool_size, pool_recycle, pool_pre_ping, and max_overflow from [database] config.
How this is hit
The async engine serves all Execution API requests that go through async session dependencies. The API server (gunicorn) creates the async engine at startup via _configure_async_session(). Without pool health settings:
The sync engine has had these settings since day one. The async engine missed them when _configure_async_session() was extracted from configure_orm() in PR #51920.
Fix
Read the same [database] config section values (pool_size, pool_recycle, pool_pre_ping, max_overflow) for the async engine. Also respect SQL_ALCHEMY_POOL_ENABLED=False by using NullPool, matching the sync engine behavior for pgbouncer setups that require it.
The create_async_metadata_engine() signature gains an optional engine_args parameter (defaulting to None for backward compatibility with existing airflow_local_settings.py overrides). Upstream PR should update the cluster-policies.rst docs to show the new signature.