observability
- Measuring OpenTelemetry Overhead Without Fooling Yourself
What OpenTelemetry costs a Spring Boot app in MiB and CPU per order, and the proofs each test cell needed before its number counted.
- Spring Boot 4 Keeps a Tracer With Tracing Off
In Spring Boot 4, management.tracing.enabled=false binds to nothing. The replacement switches off export, not the Tracer bean.
- Counts Match, Dashboards Don't: OTel Agent vs Starter
Swapping the OTel Java agent for a starter, which native requires, kept every exact count. Names, units, labels and buckets moved. What breaks, per target.
- Java 25 Changes Your Telemetry in Strings, Not Code
A 21 to 25 move compiles fine. Then ZGC series rename, pinning metrics go quiet, -javaagent sidelines the AOT cache, and going native on top drops GC metrics.
- Quarkus 12,563 vs Spring 820 (Both Numbers Are Wrong)
A Prometheus counter that resets on OOM crash-loops turned a 5x throughput advantage into a 15x deficit. The fix is six lines of awk.
- The Observability Tax: When Metrics Cost More Than Your App
Add observability to understand your app's memory usage. Watch observability consume all the memory. The JVM at 128 MB worked in Part 2. It no longer works. What Changed#One dependency: <dependency> <groupId>io.micronaut.micrometer</groupId> …