Activate and Configure ZRAM Automatically

activate_zram.sh

#!/bin/bash

# zRAM Setup Script
# Example: curl -sL https://gist.githubusercontent.com/cnmoro/32a898436388e8245fbb67cd7b6bb1e6/raw/98de143fdfe1a9c2d8649a5b5c572835c32b45e1/activate_zram.sh | sudo bash -s 4096M

set -e

# Check if running as root
if [ "$EUID" -ne 0 ]; then 
    echo "Error: This script must be run as root (use sudo)"
    exit 1
fi

# Check if size parameter is provided
if [ -z "$1" ]; then
    echo "Error: Please provide zRAM size as parameter"
    echo "Usage: $0 <size>"
    echo "Example: $0 512M"
    exit 1
fi

ZRAM_SIZE="$1"

echo "==================================="
echo "zRAM Setup Script"
echo "==================================="
echo "zRAM Size: $ZRAM_SIZE"
echo "==================================="
echo ""

# Create zram.conf in modules-load.d
echo "Creating /etc/modules-load.d/zram.conf..."
echo "zram" > /etc/modules-load.d/zram.conf

# Create zram.conf in modprobe.d
echo "Creating /etc/modprobe.d/zram.conf..."
echo "options zram num_devices=1" > /etc/modprobe.d/zram.conf

# Create udev rule
echo "Creating /etc/udev/rules.d/99-zram.rules..."
echo "KERNEL==\"zram0\", ATTR{disksize}=\"$ZRAM_SIZE\",TAG+=\"systemd\"" > /etc/udev/rules.d/99-zram.rules

# Disable traditional swap in fstab
echo "Disabling traditional swap in /etc/fstab..."
if grep -q "^/swap.img" /etc/fstab; then
    sed -i 's|^/swap.img|#/swap.img|' /etc/fstab
    echo "Traditional swap disabled in fstab"
elif grep -q "^[^#].*swap" /etc/fstab; then
    sed -i '/^[^#].*swap/s/^/#/' /etc/fstab
    echo "Swap entries commented out in fstab"
else
    echo "No active swap found in fstab"
fi

# Create systemd unit file
echo "Creating /etc/systemd/system/zram.service..."
cat > /etc/systemd/system/zram.service << 'EOF'
[Unit]
Description=Swap with zram
After=multi-user.target

[Service]
Type=oneshot 
RemainAfterExit=true
ExecStartPre=/sbin/mkswap /dev/zram0
ExecStart=/sbin/swapon /dev/zram0
ExecStop=/sbin/swapoff /dev/zram0

[Install]
WantedBy=multi-user.target
EOF

# Enable the service
echo "Enabling zram service..."
systemctl enable zram.service

echo ""
echo "==================================="
echo "zRAM setup completed successfully!"
echo "==================================="
echo ""
echo "Please reboot your system for changes to take effect:"
echo "  sudo reboot"
echo ""
echo "After reboot, verify zRAM is active with:"
echo "  swapon --show"
echo "  cat /proc/swaps"
echo "==================================="