uint32_t server_key= memcached_generate_hash_with_redistribution(ptr, group_key, group_key_length);
instance= memcached_server_instance_fetch(ptr, server_key);
uint32_t server_key= memcached_generate_hash_with_redistribution(ptr, group_key, group_key_length);
instance= memcached_server_instance_fetch(ptr, server_key);