Split Akka HTTP and Spring WebFlux tests across CI shards

[cgcote]

Summary

• split Akka HTTP 10.0 into five virtual CI projects using its existing version, forked, IAST, and Lagom tasks
• split the Spring WebFlux 5.0 base task into four balanced two-class groups, retain a catch-all for new classes, and group its forked and IAST tasks
• replace the two parent weights with measurements from CI pipeline 144209984 and rebalance the eight instrumentation shards

Stack

• Base PR: Split Lettuce tests across CI shards #12835
• This PR contains only the Akka HTTP and Spring WebFlux split.

CI Visibility measurements

Pipeline 144209984 completed successfully and provided coverage-complete weights:

• Akka HTTP: 40 passing suites; 1,361 passing and 683 skipped test executions
• largest Akka unit: 166.919 s, down 72.7% from the 612.3 s parent weight
• Spring WebFlux: 12 passing suites; 229 passing and 130 skipped test executions
• largest WebFlux unit: 122.910 s, down 75.9% from the 509.4 s parent weight
• slowest JVM 11 instrumentation shard: 26m29s, down from 34m43s (23.7%)
• aggregate JVM 11 shard compute: 10,871 s, down from 13,519 s (19.6%)
• modeled instrumentation shard max/min ratio after tuning: 1.0170
• all five Akka units land on separate shards; the five active WebFlux units span five shards

The full pipeline took 62m03s because the unrelated linux-java-spring-petclinic-startup-parallel job took 46m21s, compared with 13m50s in the parent run. The instrumentation shards finished much earlier.

Validation

• ./gradlew spotlessApply --no-daemon
• ./gradlew help -Pslot=1/8 --no-daemon
• no test suites were run locally

[dd-octo-sts]

🟢 Java Benchmark SLOs — All performance SLOs passed

Suite	Status
Startup	🟢 pass

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	13.87 s	13.98 s	[-1.5%; -0.0%] (maybe better)
startup:insecure-bank:tracing:Agent	12.86 s	12.97 s	[-1.6%; -0.1%] (maybe better)
startup:petclinic:appsec:Agent	17.11 s	17.08 s	[-0.7%; +1.0%] (no difference)
startup:petclinic:iast:Agent	16.95 s	16.31 s	[-0.4%; +8.2%] (no difference)
startup:petclinic:profiling:Agent	16.73 s	16.80 s	[-1.6%; +0.8%] (no difference)
startup:petclinic:sca:Agent	17.01 s	16.96 s	[-0.6%; +1.1%] (no difference)
startup:petclinic:tracing:Agent	16.12 s	15.68 s	[-1.5%; +7.1%] (no difference)

Commit: 6bf07f78 · CI Pipeline · Benchmarking Platform UI

---

Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.