zramctrl

#!/bin/sh


start() {
  exec awk '
  FILENAME == "/proc/cpuinfo" && ($1 == "processor" || $1 == "Processor") {
    cpucount++
    next
  }

  FILENAME == "/proc/meminfo" && $1 == "MemTotal:" {
    mem_total = int( $2 * 1024 / 2 )
    next
  }

  END {
    mem_per_cpu = int(mem_total / cpucount)

    system("modprobe zram num_devices=" cpucount)

    for (i = 0; i < cpucount; i++) {
      print mem_per_cpu > "/sys/block/zram" i "/disksize"
      system("mkswap /dev/zram" i " -L zram" i)
      swapdevs = swapdevs " /dev/zram" i
    }

    system("swapon -p 100" swapdevs)
  }
  ' /proc/cpuinfo /proc/meminfo
}

stop() {
  exec awk '
  FNR > 1 && $1 ~ /^\/dev\/zram[0-9]+$/ {
    activeswaps = activeswaps " " $1
  }

  END {
    system("swapoff" activeswaps)
    system("rmmod zram")
  }
  ' /proc/swaps
}

case $1 in
  start|stop) "$1" ;;
esac