On Mon, May 27, 2013 at 10:56 AM, 高健 <luckyjack...@gmail.com> wrote: > Hi: > Thanks for Jov's reply. > I traced it again, and found they are really for autovacuum. > I found that > some will call proc_exit() from within AutoVacLauncherMain function, > some will call proc_exit() from within AutoVacWorkerMain function. > > But I wonder why not using only a few daemon , instead of making those > processes be short life.
The short lived processes are autovacuum "worker" processes which need to exit as soon as their work is done. There does exist a daemon called autovacuum launcher, which periodically forks autovacuum worker processes to perform vacuum activity. You might want to read more about them here: http://www.postgresql.org/docs/9.2/static/routine-vacuuming.html#AUTOVACUUM -- Amit Langote -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
