Move some common scripts from multinode-demo/ to scripts/

scripts/oom-monitor.sh

@@ -0,0 +1,32 @@
+#!/bin/bash -e
+#
+# Reports Linux OOM Killer activity
+#
+
+here=$(dirname "$0")
+# shellcheck source=scripts/oom-score-adj.sh
+source "$here"/oom-score-adj.sh
+
+if [[ $(uname) != Linux ]]; then
+  exit 0
+fi
+
+syslog=/var/log/syslog
+if [[ ! -r $syslog ]]; then
+  echo Unable to read $syslog
+  exit 0
+fi
+
+# Adjust OOM score to reduce the chance that this script will be killed
+# during an Out of Memory event since the purpose of this script is to
+# report such events
+oom_score_adj "self" -500
+
+while read -r victim; do
+  echo "Out of memory event detected, $victim killed"
+  "$here"/metrics-write-datapoint.sh "oom-killer,victim=$victim killed=1"
+done < <( \
+  tail --follow=name --retry -n0 $syslog \
+  | sed --unbuffered -n 's/^.* Out of memory: Kill process [1-9][0-9]* (\([^)]*\)) .*/\1/p' \
+)
+exit 1