Disable Linux kernel from killing postgresql process
I have standard 'out-of-the-box' installation of
Linux version 3.0.1.stk64 ([email protected]) (gcc version 4.5.1 20100924 (Red Hat 4.5.1-4) (GCC) ) #1 SMP Sat Aug 13 12:53:46 EDT 2011
It has postgresql 8.4 installed as (start script)
/etc/init.d/postgresql
Data directory
/etc/postgresql/8.4/main/
My problem is that sometimes the Kernel decides to kill some of the Postgresql processes at times of low memory. I would like to inform kernel that Postgresql should not be chosen to be killed. I read from postgresql documentation (http://www.postgresql.org/docs/9.1/static/kernel-resources.html) that a command line echo -17 > /proc/self/oom_adj
can be used to avoid the kill.
I tried to add this commandline to /etc/init.d/postgresql
script but don't really know where to put it there.
Any pointers how to go about it? The scipt (/etc/init.d/postgresql
) by the way is:
#!/bin/sh
set -e
### BEGIN INIT INFO
# Provides: postgresql
# Required-Start: $local_fs $remote_fs $network $time
# Required-Stop: $local_fs $remote_fs $network $time
# Should-Start: $syslog
# Should-Stop: $syslog
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: PostgreSQL RDBMS server
### END INIT INFO
# Setting environment variables for the postmaster here does not work; please
# set them in /etc/postgresql/<version>/<cluster>/environment instead.
[ -r /usr/share/postgresql-common/init.d-functions ] || exit 0
. /usr/share/postgresql-common/init.d-functions
# versions can be specified explicitly
if [ -n "$2" ]; then
versions="$2 $3 $4 $5 $6 $7 $8 $9"
else
get_versions
fi
case "$1" in
start|stop|restart|reload|status)
for v in $versions; do
$1 $v
done
;;
force-reload)
for v in $versions; do
reload $v
done
;;
*)
echo "Usage: $0 {start|stop|restart|reload|force-reload|status} [version ..]"
exit 1
;;
esac
exit 0
You should adjust oom_adj directly to postmaster pid, add a lines like this (NOT TESTED):
pid=`cat $PGDATA/postmaster.pid | head -1`
echo -17 > /proc/$pid/oom_adj