BUG #16232: Database server connection limit exceeding

On Sat, Jan 25, 2020 at 8:40 PM PG Bug reporting form <
noreply@postgresql.org> wrote:

The following bug has been logged on the website:

Bug reference: 16232
Logged by: DEEPAK RAI B
Email address: deepakraib@gmail.com
PostgreSQL version: 9.6.9
Operating system: Core OS
Description:

Hi Team,

We are getting below error even though total connection in the database
(select count(*) from pg_stat_activity;) is not more than 10 and
max_connections are allowed 300. We are seeing below error most of the time
and only sometime it is impacting our application. Please let me know what
might be the issue?

"startup",2020-01-23 15:17:25 UTC,1999/7,0,FATAL,53300,"remaining
connection
slots are reserved for non-replication superuser connections",,,,,,,,,""

Not likely to be a bug. The issue is you've hit the max connections
allowed for non-superuser connections. You can inspect log files (possibly
after changing log settings) or plug in some active poll-based monitoring
to discover exactly how that is happening.

Follow-on questions or help is more appropriately directed to the -general
email list and not the bug reporting forum.

David J.

Hi Team,

We are actively monitoring database connections and total connection count
was not more than 14. Max connections are allowed in the database is 300.
May i know why this is occurring even though connection is not crossing its
threshold.
We are seeing below error from last 7 days and application was working fine
but yday application was not able to connect the database.Why are we
observing this behavior?

,"remaining connection
slots are reserved for non-replication superuser connections"

Regards,
Deepak

On Sun, Jan 26, 2020 at 12:18 PM David G. Johnston <
david.g.johnston@gmail.com> wrote:

Deepak Rai <deepakraib@gmail.com> writes:

We are actively monitoring database connections and total connection count
was not more than 14. Max connections are allowed in the database is 300.
May i know why this is occurring even though connection is not crossing its
threshold.

Over-aggressive setting for superuser_reserved_connections, perhaps?
Another possibility is a whole lot of uncommitted prepared transactions.

regards, tom lane

Hi Team,

Any update on this?

Regards,
Deepak

On Sun, Jan 26, 2020 at 9:36 PM Deepak Rai <deepakraib@gmail.com> wrote: