> Actually ... I take that back. I was thinking of the original purpose
> of preload_libraries, which was strictly performance optimization.
> But in the new world of plugins there may be functional reasons for
> wanting libraries to be loaded into backends --- and
> shared_preload_libraries is not isomorphic to local_preload_libraries.
> The permissions situation is different.
And, shared_preload_libraries is processed (in the postmaster) before
the shared-memory segment is created, so a shared_preload_library can
call RequestAddinShmemSpace() and RequestAddinLWLocks(), but a