每次应用重启，都会在 /dubbo/metadata/${appName} 下生成一个版本号。经过调试，发现在每次计算 revison， 会连同  pid 和 timestamp 一起计算。这样是不是有问题呢？

![image](https://user-images.githubusercontent.com/24663965/125059185-a1178700-e0dd-11eb-8271-0243d59d30b6.png)

private transient String serviceKey;
        
        private transient String matchKey;
        private transient URL url;
        public ServiceInfo() {
        }
        public ServiceInfo(URL url) {
            this(url.getServiceInterface(), url.getGroup(), url.getVersion(), url.getProtocol(), url.getPath(), null);
            this.url = url;
            Map<String, String> params = new HashMap<>();
            List<MetadataParamsFilter> filters = loader.getActivateExtension(url, "params-filter");
            if (filters.size() == 0) {
                params.putAll(
                        url.removeParameters(
                                MONITOR_KEY, BIND_IP_KEY, BIND_PORT_KEY, QOS_ENABLE,
                                QOS_HOST, QOS_PORT, ACCEPT_FOREIGN_IP, VALIDATION_KEY, INTERFACES)
                                .getParameters());
            }
            for (MetadataParamsFilter filter : filters) {
                String[] paramsIncluded = filter.serviceParamsIncluded();
                if (ArrayUtils.isNotEmpty(paramsIncluded)) {
                    for (String p : paramsIncluded) {
                        String value = url.getParameter(p);
                        if (StringUtils.isNotEmpty(value) && params.get(p) == null) {
                            params.put(p, value);
                        }
                        String[] methods = url.getParameter(METHODS_KEY, (String[]) null);
                        if (methods != null) {
                            for (String method : methods) {