Advanced RAM Use on Bash-installed Systems (2024)

This guide provides scripts and tips to optimize RAM usage on systems with Bash installed.

Table of Contents

• Free Memory Management
  • Clean RAM Script
• ZRAM Usage
  • Check ZRAM Installation
  • Create and Configure ZRAM
  • Mount ZRAM as Swap
  • ZRAM Swap as Percentage of RAM
• Additional Tips
  • Lightweight Window Manager
  • Disable Unnecessary Services
  • Close Unused Applications
  • Prioritize Processes
  • Clear Disk Cache
  • Set Process Limits

Free Memory Management

Clean RAM Script

Use this script in a cron job to clean RAM if usage exceeds 90%.

#!/bin/bash

# Set the threshold for free memory in bytes (90% of total RAM)
THRESHOLD=$(( 90 * $(grep MemTotal /proc/meminfo | awk '{print $2}') / 100 ))

# Get current free memory
FREE=$(grep MemAvailable /proc/meminfo | awk '{print $2}')

# Clean RAM if free memory is below threshold
if [ $FREE -lt $THRESHOLD ]; then
  echo "Cleaning RAM..."
  sync && echo 3 > /proc/sys/vm/drop_caches
  echo "RAM cleaned."
else
  echo "No need to clean RAM."
fi

Make the script executable and schedule it to run every 5 minutes:

chmod +x clean_ram.sh
crontab -e

Add the following line to the crontab:

*/5 * * * * /path/to/clean_ram.sh

ZRAM Usage

Check ZRAM Installation

Verify if ZRAM is installed:

lsmod | grep zram

If not installed, use your package manager to install it.

Create and Configure ZRAM

Create a ZRAM device and set its size to 1 GB with compression:

sudo modprobe zram num_devices=1
sudo zramctl -f -s 1G -t 2

Set the swappiness value:

sudo sysctl -w vm.swappiness=10

Mount ZRAM as Swap

Format and activate the ZRAM device as swap:

sudo mkswap /dev/zram0
sudo swapon /dev/zram0

Verify ZRAM usage:

sudo swapon -s

ZRAM Swap as Percentage of RAM

Create ZRAM swap space as 25% of physical RAM:

sudo zramctl --find --size $(($(free | awk '/^Mem:/{print $2}') / 4)) --mkswap
sudo swapon /dev/zram0

Additional Tips

Lightweight Window Manager

Use lightweight window managers like Xfce, LXDE, or Openbox to reduce memory usage.

Disable Unnecessary Services

Disable services to free up memory and reduce CPU usage:

sudo systemctl disable <service_name>

Close Unused Applications

Use `htop` or `top` to monitor and close unused applications.

Prioritize Processes

Adjust process priority with `nice`:

nice -n <priority> <command>

Clear Disk Cache

Free up memory by clearing disk cache:

sudo sync
sudo sh -c 'echo 3 > /proc/sys/vm/drop_caches'

Set Process Limits

Use `ulimit` to set limits on system resources for processes:

ulimit -m <memory_limit>
ulimit -t <cpu_time_limit>

These tips help optimize and clean up RAM on Bash-installed systems, improving performance and stability.

Credits

Volkan Sah