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How do I set up and configure compcache for Debian Wheezy (3.2 kernel). As far as I can understand compcache is now in the kernel and is not to be found in the debian repo either. Compcache should be accessible thorugh a /sys or /proc interface to my best knowledge but I can't figure out where it is / what it is called in Debian.

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up vote 1 down vote accepted

After some searching I found a script that explains fairly well how to turn on zram who replaces compcache. Edit: I also changed the script a bit - this is the updated version.

#! /bin/sh
# Provides:          zramstuff
# Required-Start:    $local_fs
# Required-Stop:     $local_fs
# Default-Start:     2
# Default-Stop:      0 6
# Short-Description: Enable swap to compressed ram
# Description:       Enables swapping to compressed ram

case "$1" in

       # get the number of CPUs
       num_cpus=$(grep -c processor /proc/cpuinfo)
       # if something goes wrong, assume we have 1
       [ "$num_cpus" != 0 ] || num_cpus=1

       # set decremented number of CPUs
       decr_num_cpus=$((num_cpus - 1))

       # get the amount of memory in the machine
       mem_total_kb=$(grep MemTotal /proc/meminfo | grep -E --only-matching '[[:digit:]]+')
       mem_total=$((mem_total_kb * 1024))

       # load dependency modules
       modprobe zram zram_num_devices=$num_cpus

       # initialize the devices
       for i in $(seq 0 $decr_num_cpus); do
         echo $((mem_total / num_cpus)) > /sys/block/zram$i/disksize

       # Creating swap filesystems
       for i in $(seq 0 $decr_num_cpus); do
         mkswap /dev/zram$i

       # Switch the swaps on
       for i in $(seq 0 $decr_num_cpus); do
         swapon -p 100 /dev/zram$i

       # get the number of CPUs
       num_cpus=$(grep -c processor /proc/cpuinfo)

       # set decremented number of CPUs
       decr_num_cpus=$((num_cpus - 1))

       # Switching off swap
       for i in $(seq 0 $decr_num_cpus); do
         if [ "$(grep /dev/zram$i /proc/swaps)" != "" ]; then
           swapoff /dev/zram$i

       rmmod zram
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I believe compcache will be visible as a device called /dev/ramzswap0 of type SWAP. You should be able to see it listed using blkid.

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Nope, ramzswap0 does not exists nor anything else that looks like that in /dev/ – Waxhead Apr 24 '12 at 19:03

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