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Message-ID: <484c43a4-962d-44ed-af87-e5abde63bd04@aklaver.com>
Date: Mon, 16 Jun 2025 10:21:39 -0700
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Subject: Re: Getting error "too many clients already" despite having a db
 connection limit set
To: adolfo flores <adolfoflores2211@gmail.com>,
 pgsql-general@lists.postgresql.org
References: <CADM4kyuO39mr8E_xDw4GGi2v9gCK0dq52fKj40FcsXJeKxgRrA@mail.gmail.com>
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From: Adrian Klaver <adrian.klaver@aklaver.com>
In-Reply-To: <CADM4kyuO39mr8E_xDw4GGi2v9gCK0dq52fKj40FcsXJeKxgRrA@mail.gmail.com>
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On 6/16/25 09:29, adolfo flores wrote:
> 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 

I am not understanding the above. The connection limit from the database 
side is going to be the value for max_connections. It is not clear to me 
what "...  connection limit of 30% of the max_connections setting" is 
referring to?

I suggest providing the actual numbers you are working with as well as 
the locations where the numbers are being set.


> 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.

-- 
Adrian Klaver
adrian.klaver@aklaver.com