Re: pgsql: Remove pg_dump's --no-synchronized-snapshots switch.

On 12/16/21 00:45, Tom Lane wrote:
> Remove pg_dump's --no-synchronized-snapshots switch.
>
> Server versions for which there was a plausible reason to
> use this switch are all out of support now. Leaving it
> around would accomplish little except to let careless DBAs
> shoot themselves in the foot.
>
> Discussion: https://postgr.es/m/556122.1639520324@sss.pgh.pa.us
>

Hello,

I have seen one situation where this option could have been useful even on
recent Postgres version:

Few years ago, I have seen an instance hit wraparound (1 million transactions
left) due to a bug (vacuum didn't freeze some blocks, bug has been fixed since).

I had to perform a dump/restore, but can't use parallel dump as Postgres refused
to export transaction snapshot. So the dump was ... long.

Late in the night, I didn't notice I could have used --no-synchronized-snapshots
to perform parallel dump. As Postgres didn't accept new transaction, there was
no risk of incoherent dump.

I don't know if we should keep this option. I just want to share a case where
this option could have been useful.

Regards,

--
Adrien