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Date: Fri, 20 Dec 2024 08:43:44 -0800
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Subject: Re: Intermittent errors when fetching cursor rows on PostgreSQL 16
To: Enrico Schenone <eschenone@cleistech.it>,
 pgsql-general@lists.postgresql.org
Cc: Massimo Catti <mcatti@cleistech.it>, Livio Pizzolo <lpizzolo@cleistech.it>
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From: Adrian Klaver <adrian.klaver@aklaver.com>
In-Reply-To: <4efe42a2-789c-4957-a564-25199869f6ec@cleistech.it>
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On 12/20/24 07:02, Enrico Schenone wrote:
> Hi, Adrian.
> Today I have collected a tcpdump at client side with communications 
> between application server and db server while the issue was occurring 
> one time per second on another program.
> I send you two files.
> The first one is a zipped tarball (.tgz) containing a text 
> representation of the tcpdump starting at point where it reports the 
> declaration of the failing cursor ("cu4" as you can see in the first 
> line of the file) and subsequent fetch. Consider that the client 
> application log detected the XX001 error on the first FETCH of the 
> cursor at 2024-12-20 12:17:35.175
> The second file (zipped tarball .tgz) is too big to be sent as 
> attachment, so I provide a link where it can be downloaded. It is the 
> fraction of tcpdump recorded during the program failure (occurred 
> several times). It is in .pcap format so it is possible to open it with 
> Wireshark or tcpdump -A -r
> Anyone interested can download it at 
> https://cleislabs.cleistech.it/downloads/tcpdump_out009.pcap.tgz
> 
> Consider that during the dump several different cursor was declared with 
> the name "cu4", but the one failing is the one of the first line.
> Maybe an expert (I'm not so expert) can see if the disconnection is 
> really made by the client and/or if the data returned by the server are 
> really corrupted as per XX001 SQLSTATE.

This is beyond me, someone else will need to chime in.

> 
> Best regards.
> Enrico
> 
> Il 19/12/24 22:47, Adrian Klaver ha scritto:


-- 
Adrian Klaver
adrian.klaver@aklaver.com