zramswap/zramswap.rc.d

   1 #!/bin/bash
   2
   3 . /etc/rc.conf
   4 . /etc/rc.d/functions
   5
   6 # get the number of CPUs
   7 num_cpus=$(grep -c processor /proc/cpuinfo)
   8 # if something goes wrong, assume we have 1
   9 [[ "$num_cpus" != 0 ]] || num_cpus=1
  10
  11 # set decremented number of CPUs
  12 decr_num_cpus=$((num_cpus - 1))
  13
  14 case "$1" in
  15   start)
  16     stat_busy "Enabling zram-based swap"
  17     # get the amount of memory in the machine
  18     mem_total_kb=$(grep MemTotal /proc/meminfo | grep -E --only-matching '[[:digit:]]+')
  19     mem_total=$((mem_total_kb * 1024))
  20
  21     # load dependency modules
  22     modprobe zram num_devices=$num_cpus
  23
  24     # initialize the devices
  25     for i in $(seq 0 $decr_num_cpus); do
  26       echo $((mem_total / num_cpus)) > /sys/block/zram$i/disksize
  27     done
  28
  29     # Creating swap filesystems
  30     for i in $(seq 0 $decr_num_cpus); do
  31       mkswap /dev/zram$i
  32     done
  33
  34     # Switch the swaps on
  35     for i in $(seq 0 $decr_num_cpus); do
  36       swapon -p 100 /dev/zram$i
  37     done
  38
  39     stat_done
  40   ;;
  41   stop)
  42     stat_busy "Switching off zram-based swap"
  43     # Switching off swap
  44     for i in $(seq 0 $decr_num_cpus); do
  45       if [[ "$(grep /dev/zram$i /proc/swaps)" != "" ]]; then
  46         swapoff /dev/zram$i
  47       fi
  48     done
  49
  50     rmmod zram
  51     stat_done
  52   ;;
  53   *)
  54       echo "usage: $0 {start|stop}"
  55 esac
  56
  57 exit 0