Async I/O Patterns in Production
Apply asyncio to HTTP clients, queues, and real-world pipelines.
Event-Loop Best Practices
Always use asyncio.run() as the single entry point. Avoid mixing sync and async code carelessly and never block the event loop with long CPU work.
import asyncio
async def main():
# Never: time.sleep() — blocks the event loop
# Always: await asyncio.sleep()
await asyncio.sleep(1)
asyncio.run(main())Connection Pooling
Reuse connections instead of opening a new one per request. Libraries like asyncpg and aiohttp provide built-in pools.
# pip install asyncpg
import asyncpg, asyncio
async def main():
pool = await asyncpg.create_pool(
dsn="postgresql://user:pass@host/db",
min_size=5, max_size=20
)
async with pool.acquire() as conn:
row = await conn.fetchrow("SELECT 1")
await pool.close()All lessons in this course
- Coroutines and the event loop
- await, Tasks, and Gathering
- Async Context Managers and Iterators
- Async I/O Patterns in Production