On 1/6/25 07:19, Tom Lane wrote:
Yes. sorry, I didn't include this info, you are spot on, yes this the output of ps aux .Achilleas Mantzios <a.mantzios@xxxxxxxxxxxxxxxxxxxx> writes:a query is stuck with the above, it seems it waits for parallel worker to finish, however , there are no parallel works running :You didn't explain the subject about "STAT Ssl", but if you mean that that was what ps was showing for the backend process, there's something very wrong there. According to "man ps", the "l" means l is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)
which is something that a Postgres backend should never be (in existing releases anyway). So I'm speculating that the process somehow became multi-threaded and then some wakeup signal went to the wrong thread. We've had issues with perl or python introducing multi-threading because of plperl or plpython functions doing things they probably shouldn't. Do you have any of those in your system?
Yes we have two perl functions only that I'd be happy to get rid off :
postgres@[local]/dynacom=#
select p.proname, l.lanname from pg_language l, pg_proc p
where p.prolang=l.oid and l.lanname ~* '.*perl.*';
proname | lanname
----------+---------
basename | plperlu
filetype | plperlu
(2 rows)
Nothing used in the app, just some two utility functions to
help us batch insert some attachments, guess mimetype etc. However
the calling client is Perl , based on libpg-perl (not DBI),
basically this is a descendant of DBMirror.pl (we are still
using it).
The strange
thing is that we run pgsql 16.* since November, also we run our
version of DBMirror since 2005 (and PostgreSQL since 2001) and
we never had this problem before (at least from what I know).
regards, tom lane
