Re: Amcheck verification of GiST and GIN

On Thu, Feb 2, 2023 at 12:56 PM Nikolay Samokhvalov
<samokhvalov(at)gmail(dot)com> wrote:
> I already realized my mistake – indeed, having multiple errors for 1 index
> doesn't seem to be super practically helpful.

I wouldn't mind supporting it if the cost wasn't too high. But I
believe that it's not a good trade-off.

>> I think that that problem should be solved at a higher level, in the
>> program that runs amcheck. Note that pg_amcheck will already do this
>> for B-Tree indexes.
>
>
> That's a great tool, and it's great it supports parallelization, very useful
> on large machines.

Another big advantage of just using pg_amcheck is that running each
index verification in a standalone query avoids needlessly holding the
same MVCC snapshot across all indexes verified (compared to running
one big SQL query that verifies multiple indexes). As simple as
pg_amcheck's approach is (it's doing nothing that you couldn't
replicate in a shell script), in practice that its standardized
approach probably makes things a lot smoother, especially in terms of
how VACUUM is impacted.

--
Peter Geoghegan