Example Const Vars Compare

"""Auto-generated example: Const Vars: Comparing Slices."""

import bencher as bn

class ServerBenchmark(bn.ParametrizedSweep):
    """Simulates server performance metrics under varying load conditions."""

    cpu_load = bn.FloatSweep(default=0.5, bounds=[0.0, 1.0], doc="CPU load factor")
    memory_pct = bn.FloatSweep(default=50, bounds=[10, 90], doc="Memory usage percentage")
    disk_io = bn.FloatSweep(default=0.5, bounds=[0.0, 1.0], doc="Disk I/O pressure")
    cache_enabled = bn.BoolSweep(default=True, doc="Whether caching is enabled")
    backend = bn.StringSweep(["postgres", "mysql", "sqlite"], doc="Database backend")
    log_level = bn.StringSweep(["debug", "info", "warn"], doc="Logging verbosity")
    noise_scale = bn.FloatSweep(default=0.0, bounds=[0.0, 1.0], doc="Noise scale")

    latency = bn.ResultFloat(units="ms", doc="Request latency")
    throughput = bn.ResultFloat(units="req/s", doc="Request throughput")

    def benchmark(self):
        cache_factor = 0.6 if self.cache_enabled else 1.0
        db_base = {"postgres": 1.0, "mysql": 1.1, "sqlite": 0.7}[self.backend]
        log_penalty = {"debug": 1.3, "info": 1.0, "warn": 1.0}[self.log_level]
        self.latency = (
            db_base
            * cache_factor
            * log_penalty
            * (10 + 90 * self.cpu_load + 0.5 * self.memory_pct + 30 * self.disk_io)
        )
        self.throughput = 1000 / max(self.latency, 1)
        if self.noise_scale > 0:
            import random

            self.latency += random.gauss(0, self.noise_scale * self.latency * 0.1)
            self.throughput = 1000 / max(self.latency, 1)


def example_const_vars_compare(run_cfg: bn.BenchRunCfg | None = None) -> bn.Bench:
    """Const Vars: Comparing Slices."""
    bench = ServerBenchmark().to_bench(run_cfg)
    for mem_val in [20, 50, 80]:
        bench.plot_sweep(
            title=f"cpu_load sweep with memory_pct={mem_val}",
            input_vars=["cpu_load"],
            result_vars=["latency"],
            const_vars=dict(memory_pct=mem_val, disk_io=0.5),
        )

    return bench


if __name__ == "__main__":
    bn.run(example_const_vars_compare, subsampling_divisions=4)