I find kibana will use much more memory in my host.
Here is the screenshot about htop:
Kibana has been used for 46.8% memory, while elasticsearch just used 17%, and logstash used 12.4%.
Here is the screenshot about kibana status page:
My OS is ubuntu server 14.04.4 LTS, and kibana version is 4.4.2, installed from the official repo.