we've a vm in Azure with D11(2 cores, 14GB ram) size to host our company new web erp system that consist of jboss and postgresql installed on centos 7, only 14 users login concurrently.
From time to time we experienced slow response, user would need to wait for a minute or sometimes few minutes to load a page. checked the memory using free -h, there are more than 8GB free, checked the CPU usage in azure portal which only constantly below 10%. However, the load aveerage increased during the delayed response.
when load average is below 1.0, the web application response fast and become very unresponsive when the load average rise above 1.0. I check the iotop and realize that unresponsive web app normally occur during high postgresql update and commit. May I know what is meant by 99.99% under IO> for Postgres: jboss wsemp 127.0.0.1(40291) COMMIT ? is this where the bottleneck happened? another 99.99% that caught my eye is Postgres: checkpointer process i.imgur.com/XINJhwN.png