interface ChunkLinkListItem {
    chunk: unknown;
    callback?: (err?: unknown) => void;
    next: null | ChunkLinkListItem;
}
export interface PoolOptions {
    highWaterMark?: number;
    forceDiscard?: boolean;
}
export declare class Pool {
    protected readonly highWaterMark: number;
    protected readonly forceDiscard: boolean;
    protected chunkLinkListLen: number;
    protected chunkLinkListStart: ChunkLinkListItem;
    protected chunkLinkListEnd: ChunkLinkListItem;
    constructor({ highWaterMark, forceDiscard, }: PoolOptions);
    private getOriginItems;
    /**
     * @return boolean 当前待处理的chunk数量是否超过阈值
     * */
    addChunk(chunk: unknown, callback?: ChunkLinkListItem['callback']): boolean;
    delChunks(num: number): void;
    getChunks(num: number): {
        next: any;
        chunk: unknown;
        callback?: (err?: unknown) => void;
    }[];
}
export {};