Re: Segfault during queries

Interesting! Thank you, I am seeing that we have an outdated version of
plv8 that does not match what we should be running for pg12.x, let me try
dropping that extension and recreating it with a newer version.

-Tyler

On Oct 29, 2021 at 10:27:45 AM, Scott Ribe <scott_ribe(at)elevated-dev(dot)com>
wrote:

> Of course I cannot say if this is your case, but I've been using PG since
> 2004 and every single instance* of a segfault has turned out to be caused
> by some 3rd-party extension or other. And yes, the extension was never
> related in any way to the query being run, it just corrupted memory such
> that PG would die later. So I would audit extensions, and see if any have
> been recently added, any could be removed temporarily, and so on.
>
> * It's only 2 or 3 cases in all that time, but still, it was never core PG.
>
> --
> Scott Ribe
> scott_ribe(at)elevated-dev(dot)com
> https://www.linkedin.com/in/scottribe/
>
>
>
> On Oct 29, 2021, at 8:05 AM, Tyler Brock <tyler(dot)brock(at)gmail(dot)com> wrote:
>
>
> Hi all,
>
>
> I keep getting segfaults when running queries against postgresql replicas.
> We have an ETL job that hits these nodes with many small queries (no more
> than 8 concurrently) and the box has 16 cores and plenty of I/O and ram.
>
>
> However, during this process postgresql segfaults, usually on COPY
> commands that have this shape:
>
>
> COPY
>
> (
>
> SELECT row_to_json(t)
>
> FROM (
>
> SELECT lead_tag."objectId" AS "lead_id",
>
> lead_tag."tag" AS "tag_id"
>
> FROM (
>
> SELECT "objectId",
>
> jsonb_array_elements_text("tags")
> AS tag
>
> FROM "Lead"
>
> WHERE true
>
> AND "Lead"."organization" =
> 'I6JDWAaZx5'
>
> AND tags IS NOT NULL
>
> AND "Lead"."updatedAt" >=
> '2015-01-01'
>
> AND "Lead"."updatedAt" <
> '2021-10-30T11:05:40.389773+00:00' ) AS lead_tag) t) TO stdout
>
>
> Is there anything I can do to prevent this or anything i can look at to
> try and diagnose what is happening here? I’m running Postgres 12.7 and
> cannot tell if this is a symptom of a bug or just misconfiguration.
>
>
> What I see in the error logs is:
>
>
> 2021-10-29 11:08:10 UTC:172.23.17.171(54332):postgres(at)postgres:[22200]:ERROR:
> cache lookup failed for type 0
>
> 2021-10-29 11:08:10 UTC:172.23.17.171(54332):postgres(at)postgres:[22200]:STATEMENT:
> COPY (SELECT ROW_TO_JSON(t) FROM (… the query above...) TO STDOUT
>
> 2021-10-29 11:08:10 UTC::@:[19406]:LOG: server process (PID 22200) was
> terminated by signal 11: Segmentation fault
>
>
>
> Any help would be greatly appreciated, thanks!
>
>
> -Tyler
>
>
>