Are there long-term detriments from executing an immediate shutdown and/or issuing SIGQUITs to either the parent or any child postmaster? I'm aware that PostgreSQL, upon next start, performs a WAL replay and performs other crash recovery steps. Are there certain operations, such as VACUUM ANALYZEs, CREATE INDEXs, INSERTs, UPDATEs, and/or DELETEs, for example, that are less easily recovered or less recoverable than other operations?
What might cause an operation, such as a VACUUM ANALYZE, not to exit upon receiving a SIGTERM. Are there any circumstances when a SIGQUIT could fail to cause an imminent exit (other than a process in an fundamentally unreceptive state, such as an uninterruptible sleep).