Concurrency and Performance

日期：2026-06-17 · 场景：Concurrency and Performance

📖 Vocabulary

Word	Meaning	Example
asynchronous	异步的；调用后不立即返回结果，靠回调或事件通知完成	We refactored the payment step to be asynchronous so the API can respond without waiting for the bank. 我们把支付步骤改成了异步，这样 API 不必等银行确认就能返回。
callback	回调；任务完成时被调用的函数	Register a callback that fires when the payment gateway replies, then update the order status. 注册一个回调，在支付网关应答时触发，再更新订单状态。
concurrency	并发；多个任务在同一时段交错或同时执行的能力	Raising concurrency on the worker pool lets us handle more requests at once. 提高 worker 池的并发度，能让我们同时处理更多请求。
throughput	吞吐量；单位时间内系统处理的请求数或数据量	Better throughput means fewer timeouts during peak hours. 更高的吞吐量意味着高峰时段超时更少。
latency	延迟；从发起请求到收到响应之间的时间	Our average latency doubled after the holiday sale, so we are investigating the checkout flow. 大促之后我们的平均延迟翻倍，所以正在排查结账流程。

🎧 Audio

💬 Dialogue

A: We have a serious latency problem in the checkout flow. A：我们的结账流程有严重的延迟问题。

B: Right. The numbers show our average latency doubled after the holiday sale. B：对。数据显示，大促之后我们的平均延迟翻倍了。

A: I think the root cause is the synchronous payment calls. We should make them asynchronous. A：我觉得根因是同步的支付调用，我们应该改成异步。

B: Agreed. An asynchronous design would let us return a response before the bank confirms. B：同意。异步设计能让我们在银行确认之前就返回响应。

A: We can register a callback that fires when the payment gateway replies. A：我们可以注册一个回调，在支付网关应答时触发。

B: Good. The callback can then update the order status in the background. B：好。回调再在后台更新订单状态。

A: We also need to raise concurrency on the worker pool. Right now it is capped at ten. A：我们还得提高 worker 池的并发度，现在被限制在十个。

B: Higher concurrency should lift our throughput and clear the queue faster. B：更高的并发度应该能提升吞吐量，更快清空队列。

A: Exactly. Better throughput means fewer timeouts during peak hours. A：没错。更好的吞吐量意味着高峰时段超时更少。

B: Let me draft the design doc and we can review it tomorrow. B：我来起草设计文档，我们明天评审。