redis - StackExchange.Redis 的 SETNX 超时

Question

在野外捕捉到这个随机异常:

System.Web.HttpUnhandledException (0x80004005): Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> System.TimeoutException: Timeout performing SETNX GeoIP.[REDACTED], inst: 1, mgr: Inactive, err: never, queue: 2, qu: 0, qs: 2, qc: 0, wr: 0, wq: 0, in: 0, ar: 0, clientName: PRD-VM-WEB-1, serverEndpoint: Unspecified/[REDACTED].redis.cache.windows.net:6380, keyHashSlot: 3519, IOCP: (Busy=0,Free=1000,Min=2,Max=1000), WORKER: (Busy=1,Free=32766,Min=2,Max=32767), Local-CPU: unavailable (Please take a look at this article for some common client-side issues that can cause timeouts: https://github.com/StackExchange/StackExchange.Redis/tree/master/Docs/Timeouts.md) at StackExchange.Redis.ConnectionMultiplexer.ExecuteSyncImpl[T](Message message, ResultProcessor1 processor, ServerEndPoint server) at
StackExchange.Redis.RedisBase.ExecuteSync[T](Message message,
ResultProcessor1 processor, ServerEndPoint server)

使用部署在 Azure 上的 StackExchange.Redis。

从 referenced cached document 中我可以看出看起来不错，也许 Local-CPU 不可用值是问题所在？

有谁知道是什么导致了这个抛出？

Answer 1

当您查看收到的错误时，您是否看到 BUSY 值大于 IOCP 或工作线程池的 MIN 的任何超时错误？如果是这样，线程池节流可能是原因。这通常发生在突发情况下。这通常伴随着高 CPU，这也会导致超时。此处解释了线程池节流:https://gist.github.com/JonCole/e65411214030f0d823cb#file-threadpool-md .

另外，这里有一些最佳实践:https://gist.github.com/JonCole/925630df72be1351b21440625ff2671f#best-practices-for-azure-redis