#!/bin/sh

#
# SPDX-License-Identifier: BSD-2-Clause-FreeBSD
#
# Copyright (c) 2020 Peter Holm <pho@FreeBSD.org>
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#

# VM stress. Variation of sort.sh

[ `sysctl -n vm.swap_total` -eq 0 ] && exit 0

for i in `jot 32`; do
	sort /dev/zero &
	pids="$pids $!"
done
pct=-1
start=`date '+%s'`
while [ $((`date '+%s'` - start)) -lt 300 ]; do
	sleep 10
	p=`swapinfo | tail -1 | awk '{sub("%","");print $NF}'`
	[ $p -gt $pct ] && pct=$p
	pgrep -q sort || break
done
echo "Max swap used is ${pct}%"
while pgrep -q sort; do
	kill -9 $pids > /dev/null 2>&1
	sleep 1
done
wait
exit 0