Clean VM for compacting

clean-vm.sh

#!/bin/bash

if [[ $EUID -ne 0 ]]; then
    echo "Please run as root or sudo"
    exit 1
fi

set -e

if [ -f /etc/os-release ];  then
  source /etc/os-release
  echo "Detected OS: $NAME $VERSION"
else
  ID="Unkonwn"
fi
case "$ID" in
manjaro)  CLEANCMD='yes | pacman -Scc'
    ;;
ubuntu|debian)  CLEANCMD='apt clean all && rm -f /var/lib/apt/lists/* || true'
    ;;
fedora|centos|rhel)  CLEANCMD="yum --enablerepo='*' clean all && rm -rf /var/cache/yum"
    ;;
*) echo "don't know how to clean: $ID"
   CLEANCMD=''
   ;;
esac

if [ ! -z "$CLEANCMD" ]; then
  echo "Remove Cached Packages..."
  eval $CLEANCMD
fi

echo "Removing temporary files"
rm -rf /var/tmp/*
rm -rf /tmp/*

df -l --output=target,fstype | grep -v tmpfs | grep -v /run/media/ | sed '1d' | cut -f 1 -d' ' | while IFS= read -r line
do
  preavail=$(df -k --output=avail "$line" | sed 1d)
  echo "Zeroing $preavail Kbytes from $line"
  dd if=/dev/zero of="${line}BIGFILE" bs=1M status=none 2>/dev/null || true
  sync
  rm -f "${line}BIGFILE"
done

cut -f 1 -d' ' </proc/swaps | sed 1d | while IFS= read -r line
do
  echo "Clearing $line Swap"
  swapoff "$line"
  dd if=/dev/zero of="$line" bs=1M status=none 2>/dev/null || true
  mkswap "$line"
  swapon "$line"
done