Monitoring keeps a lot of memory and creates many documents

Hello! I am using elastic and kibana.I have created an index with documents, but recently I saw that kibana and elastic keep monitoring for every day with many extra documents.Is this necessary or I can go on without them? And if yes, how can I erase them or disable them?

Look at https://www.elastic.co/guide/en/x-pack/current/monitoring-settings.html and xpack.monitoring.history.duration