debug-scripts: add a snapshot+balance stressor

This just runs snapshot and balance and snapshot delete a bunch.

Signed-off-by: Josef Bacik <[email protected]>

Author: josefbacik

snapshot-balance.sh

@@ -0,0 +1,66 @@
+#!/bin/bash
+
+COMPILEBENCH=/root/compilebench-0.6/
+DEV=/dev/nvme1n1
+MNT=/mnt/test
+SNAP_INTERVAL=1
+NUM_SNAPS=10
+
+_fail() {
+	echo $1
+	exit 1
+}
+
+_snap_thread() {
+	local i=0
+	local del=0
+	local DEL_MOD=$(( NUM_SNAPS * 2 ))
+	local DEL_SNAPS=$NUM_SNAPS
+	while [ 1 ]
+	do
+		sleep $SNAP_INTERVAL
+		btrfs sub snap $MNT $MNT/snaps/snap$i > /dev/null || \
+				_fail "failed to create snap$i"
+		i=$(( i + 1 ))
+		if [ "$(( i % DEL_MOD))" -eq "0" ]
+		then
+			for c in $(seq 1 $DEL_SNAPS)
+			do
+				btrfs subvolume delete $MNT/snaps/snap$del || \
+					_fail "failed to delete snap$del"
+				del=$((del + 1 ))
+			done
+			btrfs balance start --full-balance --bg $MNT
+			DEL_SNAPS=20
+		fi
+	done
+}
+
+_balance_thread() {
+	while [ 1 ]
+	do
+		sleep $SNAP_INTERVAL
+		btrfs balance start --full-balance $MNT || \
+			_fail "failed to balance"
+	done
+}
+
+mkfs.btrfs -f -n 4096 $DEV || _fail "couldn't mkfs"
+mount $DEV $MNT || _fail "couldn't mount"
+
+mkdir $MNT/snaps
+_snap_thread &
+SNAP_PID=$!
+
+cd $COMPILEBENCH
+for i in $(seq 0 100)
+do
+	./compilebench -i 300 -m -D $MNT || break
+done
+
+[ "$?" -ne "0"] && echo "compilebench failed"
+
+btrfs balance cancel $MNT
+kill -9 $SNAP_PID
+
+wait