making the zero write optional

provision/cleanup.sh

@@ -3,10 +3,5 @@
 set -e
 set -x
 
+# clear package cache
 yes | sudo pacman -Scc
-
-# Write zeros to improve virtual disk compaction.
-zerofile=$(/usr/bin/mktemp /zerofile.XXXXX)
-dd if=/dev/zero of="$zerofile" bs=1M || true
-rm -f "$zerofile"
-sync

provision/write_zeroes.sh

+#/bin/bash
+
+set -e
+set -x
+
+# Write zeros to improve virtual disk compaction.
+zerofile=$(/usr/bin/mktemp /zerofile.XXXXX)
+dd if=/dev/zero of="$zerofile" bs=1M || true
+rm -f "$zerofile"
+sync