Package: freedombox-setup Severity: wishlist This may help for systems with not much RAM, such as the Beaglebone Black.
--- first-run.d/03_zram | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100755 first-run.d/03_zram diff --git a/first-run.d/03_zram b/first-run.d/03_zram new file mode 100755 index 0000000..656a067 --- /dev/null +++ b/first-run.d/03_zram @@ -0,0 +1,92 @@ +#!/bin/bash + +# Because the typical deployment will be on hardware with limited +# memory resources enabling zram can help to avoid processes being +# oom killed + +# Adapted from systemd scripts at https://github.com/mystilleef/FedoraZram + +if [ ! -f /etc/modprobe.d/zram.conf ]; then + echo 'options zram num_devices=1' > /etc/modprobe.d/zram.conf +fi + +cat > /etc/systemd/system/zram.service <<EOF +[Unit] +Description=Enable compressed swap in memory using zram +After=multi-user.target + +[Service] +RemainAfterExit=yes +ExecStart=/usr/sbin/zramstart +ExecStop=/usr/sbin/zramstop +Type=oneshot + +[Install] +WantedBy=multi-user.target +EOF + +echo '#!/bin/bash - + +# 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=$((mem_total_kb * 1024)) + +# load dependency modules +modprobe zram num_devices=$num_cpus + +# initialize the devices +for i in $(seq 0 $decr_num_cpus); do + echo $((mem_total / num_cpus)) > /sys/block/zram$i/disksize +done + +# Creating swap filesystems +for i in $(seq 0 $decr_num_cpus); do + mkswap /dev/zram$i +done + +# Switch the swaps on +for i in $(seq 0 $decr_num_cpus); do + swapon -p 100 /dev/zram$i +done +exit 0' > /usr/sbin/zramstart + +cat > /usr/sbin/zramstop <<EOF +#!/bin/bash - + +# 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 + sleep 1 + fi +done + +sleep 1 +rmmod zram +exit 0 +EOF + +chmod +x /usr/sbin/zramstart +chmod +x /usr/sbin/zramstop + +# start the daemon +systemctl enable zram.service +systemctl daemon-reload +systemctl start zram.service + +exit 0 -- 2.4.1 -- System Information: Debian Release: 8.2 APT prefers stable-updates APT policy: (500, 'stable-updates'), (500, 'stable') Architecture: amd64 (x86_64) Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores) Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system)
