Ankur Mhatre
958b401f0f
Adds spring-boot-startup-time/, the companion project for BLOG-618: a runnable Spring Boot 4.1.1 application on JDK 25 that installs BufferingApplicationStartup and FlightRecorderApplicationStartup behind a system property, and a /diag/startup endpoint that computes step self time -- the number /actuator/startup does not give you and the one that names the actual culprits. Captured under docs/output/: the step tree sorted both ways, the same startup as JFR events, a +5000-class experiment putting 0.11 ms per scanned class on the classpath scan tax, the silent truncation a 2048-step buffer performs, and JDK 25 AOT cache timings (6.93 s to 4.82 s). Post body and metadata live in post/. Moves the existing Actuator project into actuator-in-production/ so the repository holds one directory per article; the root README is now an index.
19 lines
775 B
Plaintext
19 lines
775 B
Plaintext
### profile: details upstream deliberately sleeping 30s per request
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### demo.upstream.timeout-ms = 750, so the indicator gives up long before the stub replies
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$ time curl -s http://localhost:8080/actuator/health/externalApi
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{
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"details": {
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"error": "org.springframework.web.client.ResourceAccessException: I/O error on GET request for \"http://localhost:8080/stub/upstream/ping\": Read timed out",
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"url": "http://localhost:8080/stub/upstream/ping",
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"latencyMs": 753,
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"timeoutMs": 750
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},
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"status": "DOWN"
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}
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wall clock: 0.84 s
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The read timeout is what bounds this, not the endpoint. Remove setReadTimeout from
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ExternalApiHealthIndicator and this call blocks for the full 30 seconds, holding a
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Tomcat worker the whole time.
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