A tool that is being used widely by the embedded Linux community for creating mobile phone and other small-device operating systems could also be adopted as a way for Linux IT professionals to archive and store old data and records.
SquashFS is a Linux kernel source code patch that allows users to literally squash down large files and even whole directory structures for archiving in order to save disk space.
When applied to a Linux kernel, SquashFS creates a read-only file system for compressed files or directories, but still allows them to be mounted and accessed. This capability gives SquashFS an advantage over files that are compressed and archived as tar.gz (tar archives files compressed with the gzip utility), according to the developers behind SquashFS. SquashFS can squash files as large as 4GB.
SquashFS has been around since 2003, and usage of the file system has taken off largely in the embedded Linux community, where operating systems are optimized for tiny devices, and storage space is a premium. For embedded applications, the ability to compress and archive a file and still make it quickly accessible to a mobile phone or PDA's embedded operating system is key. (Companies such as MontaVista Software use SquashFS in the systems they sell to device makers such as Motorola, NEC and Panasonic).
For use in regular Linux PC or server systems, some say that the low-cost of disk space makes SquashFS less useful, since making a regularly accessed file or directory structure read-only for the sake of saving disk space is unnecessary. Still, SquashFS could be a handy tool for creating a file archiving system that still allows quick read access to storage.