Boost Linux Performance with tmpfs: Fast Cache & PHP Optimization

By default Linux mounts /dev/shm as a tmpfs filesystem, which can use RAM and swap, unlike a traditional ramdisk that requires a block device and mkfs. tmpfs is a file system that can be mounted directly.

Advantages of tmpfs:

Dynamic size.

Lightning‑fast read/write because it resides in RAM.

Data disappears after reboot, so scripts may be needed for setup.

Practical usage example:

mkdir /dev/shm/tmp
chmod 1777 /dev/shm/tmp
mount --bind /dev/shm/tmp /tmp

1. Use tmpfs for Squid cache directory:

vi /etc/squid/squid.conf
# change cache_dir line to:
cache_dir ufs /tmp 256 16 256

The first 256 means 256 MiB of memory for the cache.

2. Optimize PHP performance by storing session and temporary files on tmpfs. Since /dev/shm/tmp is bound to /tmp, adjusting php.ini to point session.save_path to /tmp (or leaving defaults) stores these files in RAM, improving speed.

After restarting services, Squid cache and PHP temporary files reside in tmpfs, providing faster access.