Running npm install on a server with only 1GB of memory can be challenging due to limited RAM. However, by enabling swap space, you can extend the virtual memory and ensure smooth operation. This blog post will guide you through the process of creating and enabling a swap partition on your server.

What is Swap?

Swap space is a designated area on a hard disk used to temporarily hold inactive memory pages. It acts as a virtual extension of your physical memory (RAM), allowing the system to manage memory more efficiently. When the system runs out of physical memory, it moves inactive pages to the swap space, freeing up RAM for active processes. Although swap is slower than physical memory, it can prevent out-of-memory errors and improve system stability.

Step-by-Step Guide to Enable Swap Space

1. Check Existing Swap Information

Before creating swap space, check if any swap is already configured:

   sudo swapon --show

1. Check Disk Partition Availability

Ensure you have enough disk space for the swap file. Use the df command:

   df -h

1. Create a Swap File

Allocate a 1GB swap file in the root directory using the fallocate program:

   sudo fallocate -l 1G /swapfile

1. Enable the Swap File

Secure the swap file by setting appropriate permissions:

   sudo chmod 600 /swapfile

Format the file as swap space:

   sudo mkswap /swapfile

Enable the swap file:

   sudo swapon /swapfile

1. Make the Swap File Permanent

To ensure the swap file is used after a reboot, add it to the /etc/fstab file:

   sudo cp /etc/fstab /etc/fstab.bak

Edit /etc/fstab to include the swap file:

   echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab

1. Optimize Swap Settings

Adjust the swappiness value to control how often the system uses swap space. A lower value reduces swap usage, enhancing performance. Check the current value:

   cat /proc/sys/vm/swappiness

Set the swappiness to 15:

   sudo sysctl vm.swappiness=15

Make this change permanent by adding it to /etc/sysctl.conf:

   echo 'vm.swappiness=15' | sudo tee -a /etc/sysctl.conf

Adjust the vfs_cache_pressure value to balance cache retention and swap usage. Check the current value:

   cat /proc/sys/vm/vfs_cache_pressure

Set it to 60:

   sudo sysctl vm.vfs_cache_pressure=60

Make this change permanent:

   echo 'vm.vfs_cache_pressure=60' | sudo tee -a /etc/sysctl.conf

Conclusion

Creating and enabling swap space allows your server to handle memory-intensive operations, such as npm install, more efficiently. While swap is not a substitute for physical RAM, it can provide a temporary solution to memory limitations, ensuring smoother performance and preventing out-of-memory errors. By following the steps outlined above, you can optimize your server's memory management and enhance its overall stability.