File metadata management in Embedded Linux

In embedded Linux systems low power consumption and memory usage are strict constraint. The problem to manage a large quantity of file metadata, that usually represents the most expensive task of such systems, is a task delegated to user space programs, generally, database based. In this work we propose how to deal with metadata at file system level with Hixosfs. Hixosfs is an ext2 based Linux filesystem, designed to easily cataloging and retrieving e-mails, musical files and logs files according final user selected metadata. The core idea is to move the problem complexity from userspace to kernel level to speed up the overall process. The implementation mainly required ext2 file system structure to be extended to store file tags, then they can be accessed and modified directly by system calls. Analysis and comparison works state this approach to be suitable for a large amount of data.