if (transactionStarted) {
registry.beginTransaction();
}
String serviceResourcePath = RegistryResources.SERVICE_GROUPS + serviceGroupName;
/* the resource should already exist */
if (registry.resourceExists(serviceResourcePath)) {
Resource serviceResource = registry.get(serviceResourcePath);
serviceResource.setProperty(RegistryResources.ServiceGroupProperties.HASH_VALUE,
hash);
registry.put(serviceResourcePath, serviceResource);
serviceResource.discard();