Re: pgBadger and postgres_fdw

On 1/21/26 08:12, Colin 't Hart wrote:

> 6. The 19 slowest queries in a 4 hour period are between 2 and 37
> minutes, with an average of over 10 minutes; they are all `fetch 100
> from c2`.
>
> The slowness itself isn't my question here; it was caused by having too
> few cores in the new environment, while the application was still
> assuming the higher core count and generating too many concurrent processes.
>
> My question is how to identify which connections / queries from
> postgres_fdw are generating the `fetch 100 from c2` queries, which, in
> turn, may quite possibly lead to a feature request for having these
> named uniquely.

My guess not.

See:

https://github.com/postgres/postgres/blob/master/contrib/postgres_fdw/postgres_fdw.c

Starting at line ~5212

fetch_size = 100;

and ending at line ~5234

/* Construct command to fetch rows from remote. */
snprintf(fetch_sql, sizeof(fetch_sql), "FETCH %d FROM c%u",
fetch_size, cursor_number);

So c2 is a cursor number.

>
> Thanks,
>
> Colin
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com