feat: add long run calculator script

scripts/long_run_calculator.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+"""Helper script that performs sustained heavy math for roughly one minute."""
+
+from __future__ import annotations
+
+import os
+import time
+
+
+def _positive_int(env_value: str, default: int) -> int:
+    """Parse a positive integer from the environment or fall back to default."""
+    try:
+        parsed = int(env_value)
+    except ValueError:
+        return default
+    return parsed if parsed > 0 else default
+
+
+def _heavy_transform(seed: int, scale: int) -> int:
+    """Iteratively mix the seed with modular multiplications to grow large numbers."""
+    modulus = (1 << 1024) - 109  # large odd modulus guarantees big intermediates
+    value = seed or 1
+    base = 65537 + (scale * 17)
+    for counter in range(1, scale + 1):
+        value = (value * (base + counter)) % modulus
+        value ^= (value >> 7)
+    return value
+
+
+def main() -> None:
+    target_seconds = _positive_int(os.getenv("LONG_RUN_TOTAL_SECONDS", "60"), 60)
+    interval_seconds = _positive_int(os.getenv("LONG_RUN_INTERVAL_SECONDS", "5"), 5)
+    work_scale = _positive_int(os.getenv("LONG_RUN_WORK_SCALE", "250000"), 250000)
+
+    steps = max(1, target_seconds // interval_seconds)
+    if steps * interval_seconds < target_seconds:
+        steps += 1
+
+    start = time.perf_counter()
+    accumulator = 1
+
+    for step in range(1, steps + 1):
+        chunk_scale = work_scale + (step * 257)
+        chunk_start = time.perf_counter()
+        accumulator = _heavy_transform(accumulator, chunk_scale)
+        compute_elapsed = time.perf_counter() - chunk_start
+        total_elapsed = time.perf_counter() - start
+
+        checksum = accumulator & ((1 << 64) - 1)
+        print(
+            f"[step {step}/{steps}] t={total_elapsed:6.2f}s "
+            f"compute={compute_elapsed:5.2f}s checksum=0x{checksum:016x}",
+            flush=True,
+        )
+
+        target_elapsed = step * interval_seconds
+        now = time.perf_counter()
+        remaining = target_elapsed - (now - start)
+        if step < steps and remaining > 0:
+            time.sleep(remaining)
+
+    final_digest = pow(accumulator, 5, (1 << 2048) - 159)
+    total_duration = time.perf_counter() - start
+    digest_bits = final_digest.bit_length()
+
+    print(
+        f"Completed in {total_duration:6.2f}s with final digest bit length {digest_bits}.",
+        flush=True,
+    )
+
+
+if __name__ == "__main__":
+    main()