Hi Tom,
thank you for your input. The DB was stuck again, I attach all logs and stack traces.
A stack trace from a COMMIT, an INSERT, an UPDATE, the wal writer, the writer, and a sequence.
Stracing the commit was stuck at: semop(3145761, {{12, -1, 0}}, 1
Please tell me what else could I do to help debugging.
Is there a way to downgrade postgresql ?