How many CPUs in play here on the PG Cluster Server,
cat /proc/cpuinfo | grep processor | wc -l
I see you got pg_stat_statements enabled, what are the SQL you
experience during this heavy load time? And does explain on them show a
lot of sorting activity that requires more work_mem.
Please
Why is 500 connections "insane". We got 32 CPU with 96GB and 3000 max
connections, and we are doing fine, even when hitting our max concurrent
connection peaks around 4500. At a previous site, we were using 2000
max connections on 24 CPU and 64GB RAM, with about 1500 max concurrent
connection
same
rows, or so), you can imagine what happens ...
Also, if part of the query required a certain amount of memory for part
of the plan, it now holds that memory for much longer too. That only
increases the change of OOM issues.
It may work fine when most of the connections are idle, but it makes
