Quarkus 12,563 vs Spring 820 (Both Numbers Are Wrong)

Fri, 03 Jul 2026 00:00:00 +0000

Part 18 of the Micronaut native image series. Follows Part 17, which found that reactive and imperative hit the same throughput ceiling. Assumes familiarity with Prometheus counters.

Two numbers that can’t both be right

The framework comparison benchmark finished. Three frameworks, same app, same k6 profile, same 256 MB native image container. The analysis script printed:

Spring Boot:  HTTP served:  820 requests   avg=2.341ms
Quarkus:      HTTP served:  12,563 requests  avg=1.892ms

Quarkus crushes Spring by 15x. Write the blog post. Ship the chart.

The Observability Tax: When Metrics Cost More Than Your App

Thu, 28 May 2026 00:00:00 +0000

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>
    <artifactId>micronaut-micrometer-registry-prometheus</artifactId>
    <scope>runtime</scope>
</dependency>

Three lines of YAML:

micrometer:
  export:
    prometheus:
      enabled: true

Prometheus endpoint exposed, micrometer collecting JVM metrics — heap, non-heap, GC pauses, threads, CPU, R2DBC pool stats. The standard production observability setup.

Prometheus on tsvinc

Quarkus 12,563 vs Spring 820 (Both Numbers Are Wrong)

Two numbers that can’t both be right

The Observability Tax: When Metrics Cost More Than Your App

What Changed