Bump jre version to 27 in ring-http-exchange

[ruroru]

Description

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PR Commands — comment on this PR to trigger (requires collaborator approval):

Command	Description
/benchmark -f <framework>	Run every test the framework subscribes to
/benchmark -f <framework> -t <test>	Run one test only
/benchmark -f <framework> --save	Run and save results (updates the leaderboard on merge)
/benchmark -f <framework> -t <test> --save	Run one test and save results
/benchmark -f <framework> --compare <other>	Measure the deltas against another framework instead of this one
/benchmark-multiple -f <fw1>,<fw2>,...	Benchmark several frameworks in one run — takes -t and --save too; saved results land in a single commit
/benchmark-multiple --save	No -f needed: benchmark and save every framework the PR touches
/benchmark-test -t <test>	Benchmark all enabled frameworks subscribed to <test> and save the results

For /benchmark, always specify -f <framework>; the flags combine in any order. Results come back as a comment with a per-profile table of RPS, p99, CPU and memory — one table per framework on multi runs. A new benchmark comment while a run is in flight queues behind it (one deep) instead of cancelling it. For multi-framework PRs (dependency bumps, same-language refactors) prefer /benchmark-multiple, which runs everything in a single job and commits all saved results together, so no run overwrites another. --compare works on single-framework runs only.

What the deltas are measured against. By default, this framework's own results published on main - answering "did this change help?". When you are tuning a variant or a successor entry, --compare re-bases them on another entry instead:

/benchmark -f genhttp --compare genhttp-kestrel

The reply states which baseline it used, and profiles the other framework does not run show n/a rather than a delta.

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Run benchmarks locally

You can validate and benchmark your framework locally with the lite script — no CPU pinning, fixed connection counts, all load generators run in Docker.

./scripts/validate.sh <framework>
./scripts/benchmark-lite.sh <framework> baseline
./scripts/benchmark-lite.sh --load-threads 4 <framework>

Requirements: Docker Engine on Linux. Load generators (gcannon, h2load, h2load-h3, wrk) are built as self-contained Docker images on first run.

[ruroru]

/benchmark -f ring-http-exchange --save

[github-actions]

👋 Benchmark request received. A collaborator will review and approve the run.

[github-actions]

⚠️ /benchmark --save aborted: main has diverged and cannot be auto-merged into this branch. Please merge or rebase main manually, push, and re-run /benchmark --save.

[github-actions]

Benchmark Results

Framework: ring-http-exchange | Test: all tests

No results captured

Full log