AW: killing idle_connections

Hi all,

do you have running something like app armor which cancels tcp connections with a typical limit of 500 ?

If yes disable and test again,

best,

Anton

Von: Walters Che Ndoh <chendohw(at)gmail(dot)com>
Gesendet: Dienstag, 1. Dezember 2020 03:50
An: pgsql-admin(at)postgresql(dot)org
Betreff: killing idle_connections

I have two DB's in prod
- DB 1 has pg12 and pgbouncer for connection pooling
- DB 2 has pg10 and F5 for connection pooling

Both DB's have a max connection of 500.
During pick hours i always run out of connections, even though i have 3 superuser reserved, my connections still go beyond 500.

So when I try to check active, idle and idle_in_transaction, this is what I get.

Count State
5
24 active
4 idle in transaction
414 idle

most of the time idle connection is at 400 plus or above 350.
So i created a script to kill connections that have been idle for 20 secs and the cron run every 1 minute. After a while, i started getting this error from developer "57P01: terminating connection due to administrator command".

I understand that connection pooling is designed to reuse idle connections and if you kill them, you are actually or probably killing a connection.

Or maybe the time i set for the script to run is too aggressive?

Or should I not run the script in the first place since connection pooling handles idle connections?

Does anyone have any suggestions to overcome my connection problems?

I have also done OS tuning and I am convinced they are okay.

Any ideas🙏

Many Thanks
Ndoh