On 15-06-2015 13:32, Jeff Janes wrote: > From http://www.postgresql.org/docs/current/static/sql-altersystem.html > > "Values set with ALTER SYSTEM will be effective after the next server > configuration reload (SIGHUP or pg_ctl reload), or after the next server > restart in the case of parameters that can only be changed at server start." > > Isn't it unfortunate that the command used for changing the > configuration file from within SQL mentions SIGHUP and pg_ctl reload, > but not "select pg_reload_conf();", as a way to activate that change? >
SIGHUP is an implementation detail. If I were to change that sentence, my preference is replace SIGHUP with pg_reload_conf.
I
disagree on SIGHUP being an implementation detail.
Using signals in IPC (inter-process communication) is a public API that should be documented when applicable. Yes, various command-line and SQL commands and functions have been provided so that one does not have to use raw signals but they are still part of the public API for the application.
Adding mention of pg_reload_conf may be warranted (probably is but I haven't made an independent evaluation) but removing SIGHUP is a separate concern and one that doesn't seem necessary.