Response from you all are very precious. @Merlin, I'm misunderstood the question. Yes, I didn't measure it. I only monitor RAM and CPU using htop (I also use nmon for disk IO, iftop for the network utilization). Did 1 connection need 1 core dedicatedly? (I was having 40-80 connections in stable condition. And when the problem happened the connections would be more than 150)
@Scott, Just before the problem happened and when the problem happened, my server didn't running out of IO/RAM/CPU. The SSD IO total usage was 25-50% (I use nmon to monitor the disk IO) The RAM total usage was 4-5GB of total 128GB (I monitor it using htop) The CPU was 100% in 2 cores, 70% in 3 cores, the other 19 cores were under 5% (I monitor it using htop) The network interface utilization was only 300-400 Mbps of total 1Gbps (I monitor it using iftop) So, maybe the 128GB RAM will never all be fully use by PostgreSQL? I will test PostgreSQL with pg_bouncer in an identical logical (OS, softwares, etc) condition and physical resource condition. Respect, FattahRozzaq
