[randomkang]

The benchmark_fb_smoke timed-boundary assertions were too tight for shared GitHub runners. Two consecutive CI runs on macOS both failed with different assertions tripped by the same cause: scheduling and I/O jitter adds ~150 ms on top of the 600 ms server-side delay, so a single call takes ~750 ms end-to-end.

• Run 1: seconds=2.2 hit the exclusive upper bound (was < 2.2).
• Run 2: seconds=2.1 passed, but p50_us=750474 exceeded 700000.

Widen the bounds while keeping the intent:

• seconds: < 2.6 still rejects a window stretched by a whole extra call (~3.4 s) but tolerates one jittered in-flight call.
• latency upper bound: use the request timeout (5 s, matching --timeout_ms=5000) instead of a fixed 700 ms; keep the 600 ms floor (the server-side delay always applies) and the p50<=max histogram ordering check.

What problem does this PR solve?

Issue Number: resolve #3731

Problem Summary:

What is changed and the side effects?

Changed:

Side effects:

• Performance effects:

• Breaking backward compatibility:

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Check List:

• Please make sure your changes are compilable.
• When providing us with a new feature, it is best to add related tests.
• Please follow Contributor Covenant Code of Conduct.

[Copilot]

🟢 Approval recommended

The changes address CI scheduling and I/O jitter while retaining the benchmark’s timing-window, latency-floor, and histogram-ordering checks.

No open issues 🎉

What changed in this PR

This PR widens the FlatBuffers benchmark smoke test’s timed assertions to tolerate scheduling and I/O jitter on shared CI runners while preserving validation of the expected timing window and server-side latency.

Changes:

• Expands the timed-window upper bound from < 2.2 to < 2.6 seconds.
• Replaces the fixed 700 ms latency ceiling with the configured 5-second request timeout.
• Retains the 600 ms latency floor and histogram ordering checks.

File	Description
example/​benchmark_fb/​smoke.py	Relaxes timed-boundary assertions and updates comments to accommodate CI jitter while preserving the benchmark’s key validation checks.

_{Review effort: Lite}

[chenBright]

LGTM