使用fs.createReadStream下载.zip文件，进程中有很多句柄（Node.js）

Question

fs.stat(file_path, function (err, stats) {
    let r = fs.createReadStream(file_path, {flags: 'r'});
    response.writeHead(200, {
        'Content-Type': mime,
        "Content-Length": stats.size,
        'Content-Disposition': 'attachment; filename=' + file_name
    });
    r.pipe(response);
    r.on('end', function () {
        r.destroy();
        response.end();
    });
    r.on('error', function (error) {
        logger.error('->>>download', error);
        r.destroy();
        response.end();
    });
});

错误日志中没有任何内容 但在/ proc / pid / fd中，句柄越来越多

一些hanle数据

72 -> /home/ec2-user/gm/uploads/respatch_scorequest_android_a.zip
73 -> /home/ec2-user/gm/uploads/cpatch_scorequest_android_a.zip
74 -> /home/ec2-user/gm/uploads/respatch_scorequest_android_a.zip
75 -> /home/ec2-user/gm/uploads/cpatch_scorequest_android_b.zip
76 -> /home/ec2-user/gm/uploads/respatch_scorequest_android_a.zip
77 -> /home/ec2-user/gm/uploads/bpatch_scorequest_android_a.zip
78 -> /home/ec2-user/gm/uploads/bpatch_scorequest_android_a.zip
79 -> /home/ec2-user/gm/uploads/respatch_scorequest_android_a.zip

Node.js：8.11.1

操作系统：Amazon Linux