"How about 'never'? Does 'never' work for you?"
Weasel says circuit_get_by_conn is his main timesink. Most of its users were just checking whether OR conns had circuits, so add a circuit count to OR conns, and check that. One was circuit_about_to_close_conn, which was doing an O(n^2) series of calls to get all circs on an OR conn, so make an O(n) function for that. Finally, circuit_get_by_edge_conn was using it as a sanity test that has been around for a while but never found any actualy insanity, so kill that. circuit_get_by_conn is finally dead, which is good, since it was never sane to begin with. svn:r5460