How to investigate deadlocks

Hello,

One of our clients running our LMS on top of PostgreSQL 13.1 created a
ticket with these messages:

2023-09-30 16:50:50.951 CEST [18117] ERROR: deadlock detected
2023-09-30 16:50:50.951 CEST [18117] DETAIL: Process 18117 waits for ShareLock on transaction 150396154; blocked by process 18187.
Process 18187 waits for ShareLock on transaction 150396155; blocked by process 18117.
Process 18117: fetch hc_d03geb
Process 18187: fetch hc_d02ben
2023-09-30 16:50:50.951 CEST [18117] HINT: See server log for query details.
2023-09-30 16:50:50.951 CEST [18117] CONTEXT: while locking tuple (38,57) in relation "d03geb"
2023-09-30 16:50:50.951 CEST [18117] STATEMENT: fetch hc_d03geb

The shown PIDs for sure are the ones of the Pos backend proc (on Linux).
Is there any chance to investigate it further?

Thanks

matthias

--
Matthias Apitz, ✉ guru(at)unixarea(dot)de, http://www.unixarea.de/ +49-176-38902045
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