Expert on Elastic Search Log Stash Kibana Beats and more

CPU load is fine with less traffic. But once traffic gets high, Elactis Search uses 100% CPU. CPU usage becomes normal once traffic gets less. RAM usage is normal always. We have a lot of docs/topics on our platform. We currently have only one node. Is it time to add another node or should we try something else first? We also need to tweak search parameters to bring better relevant results. Please advise. Elastic Search 6.5 (self-hosted) System OS: CentOS 7.5 Dedicated server configuration: Intel® Xeon® CPU E5-1650 v3 @ 3.50GHz Cores : 12 RAM: 128GB Disk: 450GB (SSD) We will also use Kibana, Logstash and Beats. We need to store all site search queries and view them in Kibana which we know is possible. But we don't know if we can extract those stored data using PHP to store in MySQL. Also is there any X-Pack alternative which supports recent ES version? Free or cheap preferred! We will also use Kibana, Logstash, Beat. We need to store all site search queries and view them in Kibana which we know is possible. But we don't know if we can extract those stored data using PHP to store in MySQL. Also is there any X-Pack alternative which supports recent ES version? Free or cheap preferred!