nordisk/holger

agent/cli/tests/integration_latency_bench_twin.rs

//! Downscaled correctness twin of the `holger.latency_tail` Bencher.
//!
//! Bench:  xtask/examples/nornir-bench.rs :: LatencyTail ("holger.latency_tail")
//! Ported from: integration_latency_tail.rs::test_tail_latency_gc_pressure
//!
//! Small-scale correctness check over the exact same
//! `holger_bench_scenarios::nexus::latency_tail` workload (512MB-heap GC-pressured
//! Nexus). The full-scale 60s tail-latency measurement lives in the bench so it
//! lands in `bench_history`.
//!
//! ## Fixture gate (NOT `--heavy`)
//!
//! The Nexus 3 testcontainer is a *fixture gate*: the scenario boots a
//! 512MB-heap Nexus and, when Docker/Podman is unavailable, returns an `is_skip`
//! error. This twin records that as a SKIP (test passes) and only asserts real
//! percentiles when a container is present. NORMAL (non-`--ignored`) test.

use holger_bench_scenarios::{nexus, Scale};

use traits::test_support::fstatus;

fn twin_scale() -> Scale {
    Scale {
        entries: 16,
        bench_secs: 1,
        threads_mt: 2,
        // entry-driven twin bench (not byte-budgeted)
        target_bytes: None,
    }
}

#[tokio::test]
#[ignore = "heavy: needs Docker/Nexus container (container = heavy; fixture-gated, runs under --heavy)"]
async fn test_latency_tail_twin_small_scale() {
    let scale = twin_scale();
    match nexus::latency_tail(&scale).await {
        Ok(o) => {
            // Container present → assert real tail-latency numbers.
            assert_eq!(o.heap_mb, 512, "GC-pressure heap must be 512 MB");
            assert!(o.samples > 0, "must have recorded latency samples");
            assert!(o.p50_ms >= 0.0, "p50 must be non-negative");
            assert!(
                o.p99_ms >= o.p50_ms,
                "p99 ({}) must be >= p50 ({})",
                o.p99_ms,
                o.p50_ms
            );
            assert!(o.throughput_mbs >= 0.0, "throughput must be non-negative");
            fstatus(
                "agent-bench",
                "latency_tail_twin",
                true,
                &format!(
                    "p50={:.2}ms p99={:.2}ms thr={:.1} MB/s n={}",
                    o.p50_ms, o.p99_ms, o.throughput_mbs, o.samples
                ),
            );
        }
        Err(e) => {
            assert!(
                nexus::is_skip(&e),
                "non-skip error from latency_tail twin: {e:#}"
            );
            eprintln!("latency_tail twin skipped (fixture gate): {e}");
            fstatus(
                "agent-bench",
                "latency_tail_twin",
                true,
                &format!("skipped: {e}"),
            );
        }
    }
}