zramcache.sh

#!/bin/sh

# turn it on if nothing passed in as args
if [ -z "$1" ]
then
	echo lz4 > /sys/block/zram0/comp_algorithm
	echo lz4 > /sys/block/zram1/comp_algorithm
	echo lz4 > /sys/block/zram2/comp_algorithm
        # 8GB of /var/tmp
        echo $((8*1024*1024*1024)) > /sys/block/zram0/disksize
        # 2GB of compressed swap
        echo $((2*1024*1024*1024)) > /sys/block/zram1/disksize

	echo $((2*1024*1024*1024)) > /sys/block/zram2/disksize

        mkswap /dev/zram1
        swapon -p 100 /dev/zram1

	# mkfs.btrfs -f -L "zram-vol" /dev/zram0
        mkfs.ext4 -F -L "zram-tmp" /dev/zram0
	mount -onoatime,nodiratime /dev/zram0 /var/tmp

	# mkfs.btrfs -f -L "zram-cache" /dev/zram2
	mkfs.ext4 -F -L "zram-cache" /dev/zram2
	mount -onoatime,nodiratime /dev/zram2 /var/cache
else
        # unload the swap devices
        if [ -b /dev/zram1 ]
        then
		echo "Unloading zram swap..."
                swapoff /dev/zram1
                sleep 0.2
		echo "Resetting zram1"
                echo 1 > /sys/block/zram1/reset
        fi
        if [ -b /dev/zram0 ]
        then
		echo "Getting rid of zram /var/tmp..."
                umount /dev/zram0 || echo "zram /var/tmp was not mounted..."
                sleep 0.2
		echo "Resetting zram0"
                echo 1 > /sys/block/zram0/reset
        fi
        if [ -b /dev/zram2 ]
        then
		echo "Getting rid of zram /var/cache..."
                umount /dev/zram2 || echo "zram /var/cache was not mounted..."
                sleep 0.2
		echo "Resetting zram2"
                echo 1 > /sys/block/zram2/reset
        fi

fi