Re: broken reading on standby (PostgreSQL 16.2)

> On 25 Apr 2024, at 11:12, Pavel Stehule <pavel.stehule@gmail.com> wrote:
>
> yesterday, I had to fix strange issue on standby server

It’s not just broken reading, if this standby is promoted in HA cluster - this would lead to data loss.
Recently I’ve observed some lost heap updates ofter OOM-ing cluster on 14.11. This might be unrelated most probably,
butI’ll post a link here, just in case [0]. In February and March we had 3 clusters with similar problem, and this is
unusuallybig number for us in just 2 months. 

Can you check LSN of blocks with corrupted tuples with pageinpsect on primary and on standby? I suspect they are frozen
onprimary, but have usual xmin on standby. 


Best regards, Andrey Borodin.

[0]
https://www.postgresql.org/message-id/flat/67EADE8F-AEA6-4B73-8E38-A69E5D48BAFE%40yandex-team.ru#1266dd8b898ba02686c2911e0a50ab47