On Mon, 2023-10-02 at 13:27 +0200, Matthias Apitz wrote: > 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? See the line: HINT: See server log for query details. Other than that, it is difficult to figure out the exact cause of a deadlock. You need to know all the statements that were run in these transactions, which probably requires deeper knowledge of the application. Yours, Laurenz Albe
