Feedback-ID: ia2694551:Fastmail
Date: Sun, 6 Oct 2024 20:37:18 +0200
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: KK CHN <kkchn.in@gmail.com>
Cc: pgsql-general <pgsql-general@postgresql.org>
Subject: Re: CLOSE_WAIT pileup and Application Timeout
Message-ID: <202410061837.u5y5zwsxcpfb@alvherre.pgsql>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <CAKgGyB91QVCOFp+3vAcMDAauAPQ+TOVWrJxwcVAtYxaLxXaz4Q@mail.gmail.com>
Archived-At: <https://www.postgresql.org/message-id/202410061837.u5y5zwsxcpfb%40alvherre.pgsql>
Precedence: bulk

On 2024-Oct-04, KK CHN wrote:

> The mobile tablets are installed with the android based vehicle
> tracking app which updated every 30 seconds its location fitted inside the
> vehicle ( lat long coordinates) to the PostgreSQL DB through the java
> backend application to know the latest location of the vehicle and its
> movement which will be rendered in a map based front end.
> 
> The vehicles on the field communicate  via 443 to   8080 of the Wildfly
> (version 27 ) deployed with the vehicle tracking application developed with
> Java(version 17).

It sounds like setting TCP keepalives in the connections between the
Wildfly and the vehicles might help get the number of dead connections
down to a reasonable level.  Then it's up to Wildfly to close the
connections to Postgres in a timely fashion.  (It's not clear from your
description how do vehicle connections to Wildfly relate to Postgres
connections.)

I wonder if the connections from Wildfly to Postgres use SSL?  Because
there are reported cases where TCP connections are kept and accumulate,
causing problems -- but apparently SSL is a necessary piece for that to
happen.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/
Thou shalt study thy libraries and strive not to reinvent them without
cause, that thy code may be short and readable and thy days pleasant
and productive. (7th Commandment for C Programmers)