transitory/dist/types/cache/bounded/CountMinSketch.d.ts

In-memory cache with high hit rates via LFU eviction. Supports time-based expiration, automatic loading and metrics.

import { KeyType } from '../KeyType';
/**
 * Count-min sketch suitable for use with W-TinyLFU. Similiar to a regular
 * count-min sketch but with a few important differences to achieve better
 * estimations:
 *
 * 1) Enforces that the width of the sketch is a power of 2.
 * 2) Uses a reset that decays all values by half when width * 10 additions
 *    have been made.
 */
export declare class CountMinSketch {
    private readonly width;
    private readonly depth;
    readonly maxSize: number;
    readonly halfMaxSize: number;
    readonly slightlyLessThanHalfMaxSize: number;
    private additions;
    readonly resetAfter: number;
    private table;
    constructor(width: number, depth: number, decay: boolean);
    private findIndex;
    update(hashCode: number): void;
    estimate(hashCode: number): number;
    private performReset;
    static hash(key: KeyType): number;
    static uint8(width: number, depth: number, decay?: boolean): CountMinSketch;
}