Further to this ... I was just doing some measurements to see how much
it'd add to backend startup time if we start using pg_strong_random()
to set the initial random seed. The answer, at least on my slightly
long-in-the-tooth RHEL6 box, is "about 25 usec using /dev/urandom,
or about 80 usec using OpenSSL". So I'm wondering why configure is
coded to prefer OpenSSL.
I'm going to go do some timing checks on some other platforms, but
this result suggests that we may need to question that choice.
regards, tom lane