dmsetup remove_all
wipefs -a --force /dev/sdb1
mkfs -t btrfs /dev/sdb1
mkdir -p /fs/sdb1
mount -t btrfs /dev/sdb1 /fs/sdb1
sync
echo 3 > /proc/sys/vm/drop_caches

for cpu_dir in /sys/devices/system/cpu/cpu[0-9]*
do
	online_file="$cpu_dir"/online
	[ -f "$online_file" ] && [ "$(cat "$online_file")" -eq 0 ] && continue

	file="$cpu_dir"/cpufreq/scaling_governor
	[ -f "$file" ] && echo "performance" > "$file"
done

filebench -f /lkp/benchmarks/filebench/share/filebench/workloads/varmail.f
sleep 100
rm -rf /fs/sdb1/bigfileset