Message-ID: <37ae75bc-6385-4e41-9a48-e03e7884bcf3@vondra.me>
Date: Wed, 15 Jan 2025 21:27:41 +0100
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Subject: Re: Data Out of Sync with Physical Streaming Replication
To: Tim Gerber <tggerber@gmail.com>, pgsql-general@lists.postgresql.org
References: <CAPKih1xk03YbvGtFpBVg=ePr081gAqQ_BGuNvQZ3BAo8DWb+rw@mail.gmail.com>
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From: Tomas Vondra <tomas@vondra.me>
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On 1/15/25 19:50, Tim Gerber wrote:
> Hi All,
>
>...
>
> Archive mode is on.   I ran pg_amcheck and everything came back clean. I
> know synchronous replication is an option, but it feels like something
> else is going on and would like to get to the bottom of it.
> 
> Any ideas on what could be causing this?  I’m planning on turning on
> data_checksums and running pg_checksums to see if any corruption is found.
> 

No idea. If the storage has some issues (which is the only thing data
checksums could catch, in some cases), then anything is possible.

I think it'd be interesting to compare the tuples returned on primary
vs. standby, including system columns etc. Ideally using pageinspect.
That might tell you what exactly is the difference, and perhaps also say
which XID to look at.

regards

-- 
Tomas Vondra