Getting error "too many clients already" despite having a db connection limit set

Hello Team,

I hope you can help me with an issue we're experiencing. We have an app
running on Kubernetes that opens a huge number of connections within a
couple of seconds.

The database that the app connects to, is configured with a connection
limit of 30% of the max_connections setting. Despite this limit being set
for that database, we're seeing the following errors in the PostgreSQL logs:

FATAL: sorry, too many clients already
FATAL: remaining connection slots are reserved for roles with the
SUPERUSER attribute

Is it expected behavior to reach the max_connections limit when that app
opens many connections in a short period of time, even if a connection
limit is set for that database and everything else uses no more than 10% of
the max_connections?

Or any idea on what could be happening?

Regards.

Adolfo F.