以下是配置HttpClient代码

private static CloseableHttpClient init() {
    try {
        PrivateKey privateKey = PemUtil.loadPrivateKey(
                new ByteArrayInputStream(merchantPrivateKey.getBytes(StandardCharsets.UTF_8)));

        CertificatesManager certificatesManager = CertificatesManager.getInstance();
        certificatesManager.putMerchant(merchantId, new WechatPay2Credentials(merchantId,
                new PrivateKeySigner(merchantSerialNumber, privateKey)), apiV3Key.getBytes(StandardCharsets.UTF_8));
        verifier = certificatesManager.getVerifier(merchantId);

        //...
        CloseableHttpClient httpClient = WechatPayHttpClientBuilder.create()
                .withMerchant(merchantId, merchantSerialNumber, privateKey)
                .withValidator(new WechatPay2Validator(verifier))
                .evictExpiredConnections() // 开启回收空闲线程
                .evictIdleConnections(3L, TimeUnit.SECONDS)     // 30秒回收空闲连接
                .setMaxConnPerRoute(300).setMaxConnTotal(1000)
                .build();

        return httpClient;
    } catch (Exception e) {
        e.printStackTrace();
    }
    return null;
}

以下是调用api接口代码
private static <T extends WechatBaseResponse> T execute(String url, Object params, boolean isPost, Class<T> tClass) {
    long startTime = System.currentTimeMillis();
    String message = JsonUtils.toJsonString(params);
    T t = null;
    try {

        HttpUriRequest request;
        if (isPost) {
            HttpPost httpPost = new HttpPost(url);
            httpPost.addHeader("Accept", "application/json");
            httpPost.addHeader("Content-type", "application/json; charset=utf-8");
            httpPost.setEntity(new StringEntity(JsonUtils.toJsonString(params), "utf-8"));
            request = httpPost;
        } else {
            HttpGet httpGet = new HttpGet(url);
            httpGet.addHeader("Accept", "application/json");
            request = httpGet;
        }

        CloseableHttpResponse response = httpClient.execute(request);
        String result = EntityUtils.toString(response.getEntity());
        t = JsonUtils.parseObject(result, tClass);
        logger.info("【微信】请求 url={} 请求参数={} 响应数据={} 处理时间={}ms", url, message, result, System.currentTimeMillis() - startTime);
    } catch (IOException e) {
        logger.error("【微信】调用异常 url={} 请求参数={}", url, message, e);
        try {
            t = tClass.newInstance();
            t.setCode(CodeEnum.ERROR.getCode());
            t.setMessage(CodeEnum.ERROR.getMsg());
        } catch (Exception ex) {
        }
    }
    return t;
}

在并发高的时候"处理时间"能有十几秒, 这个问题怎么解决? 是我配置有问题, 还是哪里有问题?