I noticed that in standalone mode, WAL segments don't seem to be
recycled. This could get problematic if you're forced to vacuum large
tables in that mode and space for WAL is short.
I can reproduce in HEAD easily by doing a large bulk insertion in
standalone mode. If I stop the server, start in normal mode and
shutdown (or checkpoint), the extra segments go away as expected.
This was reported in pgsql-es-ayuda yesterday.
--
Álvaro Herrera <alvherre@alvh.no-ip.org>