Debugging a Production Incident

日期：2026-06-17 · 场景：Debugging a Production Incident

📖 Vocabulary

Word	Meaning	Example
session	会话（客户端与服务端的一次交互状态保持）	The user's session expired after 30 minutes of inactivity. 用户会话在 30 分钟无操作后过期。
shim	兼容垫片（补齐旧环境缺失 API 的代码层）	We added a polyfill shim to support fetch on legacy browsers. 我们加了 polyfill 垫片以在旧浏览器上支持 fetch。
queue	队列（先进先出的待处理任务缓冲）	Failed jobs get retried from the dead-letter queue. 失败的任务从死信队列重试。
throttle	限流（控制请求速率防过载）	The API will throttle requests if you exceed 100 per second. 如果超过每秒 100 次请求，API 会进行限流。
mutable	可变的（运行时可被修改的状态）	Prefer immutable data structures to avoid race conditions. 优先用不可变数据结构以避免竞态条件。

A: The dashboard is showing a spike in 500 errors. Something just broke in production. A：仪表盘显示 500 错误激增。生产环境刚出问题了。

B: Let me check the logs. It looks like the session store is timing out under load. B：我看下日志。看起来是会话存储在高负载下超时。

A: Could be the new memory cache. Is the state mutable across worker threads? A：可能是新内存缓存的问题。状态在工作线程间是可变的吗？

B: Yes, that is probably the race condition. We should switch to immutable snapshots. B：是的，那大概就是竞态条件。我们应该切换到不可变快照。

A: Agreed. Also, the retry queue is backing up because failed jobs are not draining. A：同意。另外，重试队列在积压，失败任务排不出去。

B: Right. Let us throttle incoming requests for now so the system can catch up. B：对。我们先对进来的请求限流，让系统缓一缓。

A: Good call. Do we need a shim for the older clients hitting the deprecated endpoint? A：好主意。需要为访问废弃接口的旧客户端加个垫片吗？

B: Only if they keep retrying. Let me deploy the rate limit first and watch the metrics. B：只有它们一直重试才需要。我先部署限流，然后盯一下指标。