Update documentation about SIGKILL of postmaster.

Removing shared memory and semaphores in response to server start
failure often masks the real problem, a live process associated with the
data directory; see commit 5a907404b5.
Since 9.6, it's rarely necessary to kill subprocesses manually.  (When
it is necessary, that commit's HINT will say as much, in all supported
versions.)
This commit is contained in:
Noah Misch 2019-06-08 10:12:26 -07:00
parent f2c71cb71f
commit a806b14a11

View File

@ -1685,14 +1685,12 @@ $ <userinput>kill -INT `head -1 /usr/local/pgsql/data/postmaster.pid`</userinput
<important>
<para>
It is best not to use <systemitem>SIGKILL</systemitem> to shut down
the server. Doing so will prevent the server from releasing
shared memory and semaphores, which might then have to be done
manually before a new server can be started. Furthermore,
<systemitem>SIGKILL</systemitem> kills the <command>postgres</command>
process without letting it relay the signal to its subprocesses,
so it will be necessary to kill the individual subprocesses by hand as
well.
It is best not to use <systemitem>SIGKILL</systemitem> to shut down the
server. Doing so will prevent the server from releasing shared memory and
semaphores. Furthermore, <systemitem>SIGKILL</systemitem> kills
the <command>postgres</command> process without letting it relay the
signal to its subprocesses, so it might be necessary to kill the
individual subprocesses by hand as well.
</para>
</important>