Nathan Bossart <nathandboss...@gmail.com> writes: > While working on an idea from another thread [0], I noticed that each of > max_connections, max_worker_process, max_autovacuum_workers, and > max_wal_senders have a check hook that verifies the sum of those GUCs does > not exceed a certain value. Then, in InitializeMaxBackends(), we do the > same check once more. Not only do the check hooks seem redundant, but I > think they might sometimes be inaccurate since some values might not yet be > initialized.
Yeah, these per-variable checks are inherently bogus. If we can get of them and make the net user experience actually better, that's a win-win. It seems easier to do for these because they can't change after server start, so there can be one well-defined time to apply the consistency check. IIRC, we have some similar issues in other hooks for variables that aren't PGC_POSTMASTER, so it's harder to see how we might get rid of their cross-checks. That doesn't make them less bogus though. regards, tom lane