Improve handling of OOM score adjustment in sample Linux start script.

Per a suggestion from Christoph Berg.
This commit is contained in:
Tom Lane 2014-07-01 17:23:16 -04:00
parent 5a421a47eb
commit f23425fa95
1 changed files with 19 additions and 15 deletions

View File

@ -42,18 +42,17 @@ PGLOG="$PGDATA/serverlog"
# It's often a good idea to protect the postmaster from being killed by the
# OOM killer (which will tend to preferentially kill the postmaster because
# of the way it accounts for shared memory). Setting the OOM_SCORE_ADJ value
# to -1000 will disable OOM kill altogether, which is a good thing for the
# postmaster, but not so much for individual backends. If you enable this,
# also uncomment the DAEMON_ENV line, which will instruct backends to set
# their OOM adjustments back to the default setting of zero.
#OOM_SCORE_ADJ=-1000
#DAEMON_ENV="PG_OOM_ADJUST_FILE=/proc/self/oom_score_adj"
# of the way it accounts for shared memory). To do that, uncomment these
# three lines:
#PG_OOM_ADJUST_FILE=/proc/self/oom_score_adj
#PG_MASTER_OOM_SCORE_ADJ=-1000
#PG_CHILD_OOM_SCORE_ADJ=0
# Older Linux kernels may not have /proc/self/oom_score_adj, but instead
# /proc/self/oom_adj, which works similarly except the disable value is -17.
# For such a system, uncomment these two lines instead.
#OOM_ADJ=-17
#DAEMON_ENV="PG_OOM_ADJUST_FILE=/proc/self/oom_adj"
# /proc/self/oom_adj, which works similarly except for having a different
# range of scores. For such a system, uncomment these three lines instead:
#PG_OOM_ADJUST_FILE=/proc/self/oom_adj
#PG_MASTER_OOM_SCORE_ADJ=-17
#PG_CHILD_OOM_SCORE_ADJ=0
## STOP EDITING HERE
@ -80,13 +79,19 @@ test -x $DAEMON ||
fi
}
# If we want to tell child processes to adjust their OOM scores, set up the
# necessary environment variables. Can't just export them through the "su".
if [ -e "$PG_OOM_ADJUST_FILE" -a -n "PG_CHILD_OOM_SCORE_ADJ" ]
then
DAEMON_ENV="PG_OOM_ADJUST_FILE=$PG_OOM_ADJUST_FILE PG_OOM_ADJUST_VALUE=$PG_CHILD_OOM_SCORE_ADJ"
fi
# Parse command line parameters.
case $1 in
start)
echo -n "Starting PostgreSQL: "
test x"$OOM_SCORE_ADJ" != x && echo "$OOM_SCORE_ADJ" > /proc/self/oom_score_adj
test x"$OOM_ADJ" != x && echo "$OOM_ADJ" > /proc/self/oom_adj
test -e "$PG_OOM_ADJUST_FILE" && echo "$PG_MASTER_OOM_SCORE_ADJ" > "$PG_OOM_ADJUST_FILE"
su - $PGUSER -c "$DAEMON_ENV $DAEMON -D '$PGDATA' &" >>$PGLOG 2>&1
echo "ok"
;;
@ -98,8 +103,7 @@ case $1 in
restart)
echo -n "Restarting PostgreSQL: "
su - $PGUSER -c "$PGCTL stop -D '$PGDATA' -s -m fast -w"
test x"$OOM_SCORE_ADJ" != x && echo "$OOM_SCORE_ADJ" > /proc/self/oom_score_adj
test x"$OOM_ADJ" != x && echo "$OOM_ADJ" > /proc/self/oom_adj
test -e "$PG_OOM_ADJUST_FILE" && echo "$PG_MASTER_OOM_SCORE_ADJ" > "$PG_OOM_ADJUST_FILE"
su - $PGUSER -c "$DAEMON_ENV $DAEMON -D '$PGDATA' &" >>$PGLOG 2>&1
echo "ok"
;;