feat(db): configurable connection pool tuning for MySQL / PostgreSQL#72
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pushiwuhua7 wants to merge 1 commit into
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feat(db): configurable connection pool tuning for MySQL / PostgreSQL#72pushiwuhua7 wants to merge 1 commit into
pushiwuhua7 wants to merge 1 commit into
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Without pool_pre_ping=True, asyncpg leaves cancelled-task connections in a broken state inside the pool, causing the next checkout to hang indefinitely under concurrent load. Expose the standard SQLAlchemy pool knobs (size / max_overflow / recycle / pre_ping / timeout) via env vars with sensible defaults, applied to non-SQLite engines only. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Why
Without
pool_pre_ping=True,asyncpgleaves connections that wereinterrupted by task cancellation (CancelledError) in a half-broken
state inside the SQLAlchemy pool. The next checkout of such a
connection hangs indefinitely, which under concurrent load presents
as the whole app stalling — even though no obvious error surfaces.
The default
AsyncAdaptedQueuePool(pool_size=5, max_overflow=10,pool_timeout=30s) is also too small for production deployments and
provides no recycle behavior to survive managed-PG idle timeouts.
What
Expose the standard SQLAlchemy pool knobs via env vars, applied to
non-SQLite engines only:
DB_POOL_SIZEDB_MAX_OVERFLOWDB_POOL_PRE_PINGDB_POOL_TIMEOUTSQLite path is unchanged.
Test
agent execution no longer occurs after enabling
pool_pre_ping