Function evaluateLoadSignalSample

packages/core/src/autoscaling/load_signal.ts:188–215

(sample: LoadSnapshot[], overloadedRatio: number)

 * evaluation logic used by `SystemStatus` for all signal types.
 */
export function evaluateLoadSignalSample(sample: LoadSnapshot[], overloadedRatio: number): ClientInfo {
    if (sample.length === 0) {
        return {
            isOverloaded: false,
            limitRatio: overloadedRatio,
            actualRatio: 0,
        };
    }

    const weights: number[] = [];
    const values: number[] = [];

    for (let i = 1; i < sample.length; i++) {
        const previous = sample[i - 1];
        const current = sample[i];
        const weight = +current.createdAt - +previous.createdAt;
        weights.push(weight || 1); // Prevent errors from 0ms long intervals (sync) between snapshots.
        values.push(+current.isOverloaded);
    }

    const wAvg = sample.length === 1 ? +sample[0].isOverloaded : weightedAvg(values, weights);

    return {
        isOverloaded: wAvg > overloadedRatio,
        limitRatio: overloadedRatio,
        actualRatio: Math.round(wAvg * 1000) / 1000,
    };
}