Yes I'm using extensions - A bunch of them but I'm guessing it's likely ogr_fdw that will be causing the issue as I've only seen this on days when someone has imported data using ogr_fdw.
Thomas Munro <thomas.munro@enterprisedb.com> writes: > We could probably improve that situation by making syscache lookups > (and probably other things too) fail when called from _PG_init() in > regular backends so that extension authors are made aware of this > hazard, or perhaps go the other way and change the order we do things > in parallel workers.
Hmm. There's an argument to be made for the latter: we don't really want stuff failing in parallel workers if it works fine normally.
On the other hand, it seems clear to me that we *don't* want extensions to be doing stuff like syscache lookups in _PG_init(), because that would prevent them from working as shared_preload_libraries entries.
And on the third hand, intentionally breaking code that used to work isn't likely to win us many friends either. So I'm not sure that your first option is really tenable. Perhaps we could get away with doing it in HEAD and not back-patching ... but that does little for existing problems.
