Spring 启动测微计计数取消

Question

This is more of a Meta question than a clear technical issue.

I am monitoring a Spring Boot (2.2.6) service with Micrometer (1.4.1). The application is Reactor based and is healthy, but every now and then following value is increased one click:

reactor_flow_duration_seconds_count{flow="requests", status="cancelled"}

The application has 2000 req/min and the cancel happens somewhere 1-10 times a day. I've checked the Micrometer source code and it counts on cancel but there is no cancel invocations in the code. There are FluxToMono events and such that trigger a cancel, those are deep down in Netty so nothing we should care about.

What is the purpose of counting cancel invocations in Micrometer? Is it useful, do I miss the purpose?

Answer 1

Short answer is, the cancel counter doesn't make sense to monitor. There's nothing critical with that value and cancel invocation happen in normal execution.