EFS

The Extent File System was the default filesystem used by IRIX from GL2-W2.4 (pre-IRIX 4.x) through IRIX 5.3. Additionally, it was the filesystem used for all CDs produced for IRIX by SGI.

History

EFS was introduced in GL2-W2.4, a pre-IRIX System V based product to replace the original System V UFS. It was deprecated starting in 1994, with the release of an IRIX 5.3 XFS distribution, and replaced by XFS with IRIX 6.0 on all new installs.

Details

The EFS filesystem is relatively primitive by modern standards, being a synchronous (non-journaling, no soft updates) filesystem with a fixed block size of 512 bytes.

• Block size: 512-bytes
  • Block 0: unused or contains a bootstrap program
  • Block 1: superblock, contains file system metadata
• Maximum file system size: 8GB (224 or 16777214 blocks)
• Maximum individual file size: 2GB
• Number of fixed-files created by mkfs: 9