并发与反压
限制并行工作量，让服务器保持健康。
并发与反压 是 CoddyKit 上的免费 MCP Academy 课时。 这是第 2 节课，共 4 节。 你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。 这是 MCP Academy 学习路径的一部分，你的进度在网页和 CoddyKit 应用中同步。 MCP Academy 课程共包含 4 节课。
本课时的部分内容尚未翻译，以英文显示。
Async Isn't Infinite
Async lets you run many calls at once, but every in-flight task still uses memory and connections. Unbounded concurrency can sink a server. 💥
What Backpressure Means
Backpressure is how a busy server pushes back on incoming work, slowing or queuing it instead of trying to do everything at once.
Cap Parallel Work
A semaphore sets a ceiling on how many tasks run in parallel, so the server takes on only as much as it can safely handle.
sem = asyncio.Semaphore(10)
async with sem:
await do_work()Bound Your Connection Pools
Give database and HTTP pools a max size. Past it, new calls wait for a free connection rather than opening endless ones.
Queue, Don't Drop
When you are at capacity, let extra calls queue briefly. Short, bounded waits beat crashing under a sudden burst of requests.
Bound the Queue Too
An unbounded queue just hides the overload until memory runs out. Cap the queue length and reject work once it is full.
Reject Fast When Full
If the server is saturated, return a clear busy error quickly so the client can retry, rather than letting calls hang forever.
Add Timeouts Everywhere
Pair limits with timeouts so a single stuck upstream cannot hold a slot indefinitely and slowly starve every other request.
async with asyncio.timeout(5):
await call_upstream()Watch In-Flight Counts
Track how many tasks are active right now. Rising in-flight counts are your earliest warning that load is outpacing capacity.
Tune Limits to Reality
Pick limits from measured behavior, not guesses. Load-test, watch latency, and raise or lower caps until the server stays stable.
Stay Healthy Under Load
Done well, backpressure keeps a server stable: it serves what it can, defers the rest, and never tips into a crash.
Quick Check
What does backpressure protect a server from?
Recap: Bound the Load
You capped parallel work with semaphores, bounded pools and queues, added timeouts, and rejected fast when full, keeping the server healthy. ✅
常见问题解答
「并发与反压」课时是免费的吗？
是的 — 「并发与反压」的完整文本可在网页上免费阅读。要进行交互式练习（内置代码编辑器和全天候 AI 导师）并解锁 MCP Academy 课程的其余内容，请升级到 CoddyKit PRO。 MCP Academy 课程共包含 4 节课。
「并发与反压」这节课中我会学到什么？
限制并行工作量，让服务器保持健康。 你通过在浏览器中直接运行的动手代码来练习 MCP Academy，全天候 AI 导师会在你学习这节课的过程中回答你的问题。
学习 MCP Academy 需要有经验吗？
无需任何先前经验。CoddyKit 上的 MCP Academy 课程适合初学者到高级学习者，你可以从这里开始或从头开始，按照自己的节奏学习。 这是第 2 节课，共 4 节。
「并发与反压」课时需要多长时间？
大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动，所以你能稳步进步，并在网页和应用中从离开的地方继续。
我能在这节 MCP Academy 课中编写并运行代码吗？
能。每节 MCP Academy 课都包含内置代码编辑器，你可以在浏览器中直接编写并运行真实代码，并获得即时 AI 反馈 — 无需本地设置。