[ISSUE #3922] method createServiceIfAbsent in ServiceManager require sync

[a7217107]

method createServiceIfAbsent in ServiceManager require sync #3922

What is the purpose of the change

change method createServiceIfAbsent sync

Brief changelog

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[CLAassistant]

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[KomachiSion]

lock in this may affect the performance.
I think fix like following will be better

    public void putService(Service service) {
        if (!serviceMap.containsKey(service.getNamespaceId())) {
            synchronized (putServiceLock) {
                if (!serviceMap.containsKey(service.getNamespaceId())) {
                    serviceMap.put(service.getNamespaceId(), new ConcurrentHashMap<>(16));
                }
            }
        }
        *serviceMap.get(service.getNamespaceId()).putIfAbsent(service.getName(), service);
    }

    private void putServiceAndInit(Service service) throws NacosException {
        putService(service);
        *service = getService(service.getNamespaceId(), service.getName());
        service.init();
        consistencyService.listen(KeyBuilder.buildInstanceListKey(service.getNamespaceId(), service.getName(), true), service);
        consistencyService.listen(KeyBuilder.buildInstanceListKey(service.getNamespaceId(), service.getName(), false), service);
        Loggers.SRV_LOG.info("[NEW-SERVICE] {}", service.toJSON());
    }

What's your think about

[a7217107]

you are right, "synchronized (this)" in this method will affect the performance, your plan is better