On 8/14/18 10:05 AM, Tomas Vondra wrote:
> ...
>
> I take that back - I can reproduce the crashes, both with and without
> the patch, all the way back to 9.6. Attached is a bunch of backtraces
> from various versions. There's a bit of variability depending on which
> pgbench script gets started first (insert.sql or vacuum.sql) - in one
> case (when vacuum is started before insert) the crash happens in
> InitPostgres/RelationCacheInitializePhase3, otherwise it happens in
> exec_simple_query.
>
> Another observation is that the failing COPY is not necessary, I can
> reproduce the crashes without this (so even with wal_level=replica).
>
BTW I have managed to reproduce this on an old test server. If anyone
wants to take a look, I can arrange ssh access to that machine (for
trustworthy developers). Let me know.
regards
--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services