Linux XFS and IRIX XFS

The XFS filesystem under Linux differs from the XFS filesystem under IRIX in the following ways:

• For XFS Linux 1.0, the filesystem blocksize is limited to the size of a memory page.
• The interface with the kernel (system calls) for Access Control Lists (ACLs) and Extended Attributes (EAs) is different in XFS/Linux compared with IRIX. However, the user level libraries for both ACLs and EAs are exactly the same in Linux and IRIX. Thus ACL or EA application code can be exactly the same.
• Unwritten extents are not supported in XFS Linux 1.0.
• Linux XFS filesystems are limited to 2 Terabytes in size due to limitations in the Linux block device I/O layers.
• The maximum accessible file offset of a Linux XFS file is 16 Terabytes on 4K page size and 64 Terabytes on 16K page size.
• Linux xfsdump/xfsrestore does not support:

  • multiple tape devices using multiple -f options
  • new IRIX 6.5.12 dump option, -z (prune large files)
  • DMAPI related options of -a and -D

  Linux xfsdump/xfsrestore does, however, have the added capabilites of unrestricted use of the -b option for blocksize specification and remote dumping/restoring between Linux and IRIX hosts.

• IRIX XFS filesystems support user and project quotas. Linux XFS filesystems support user and group quotas.
• Under IRIX, external logs are specified using a volume manager, XLV or XVM. Under Linux, external logs can be specified with extensions to the -l option of mkfs.
• The quotactl(2) system call interface differs between IRIX and Linux, and the Linux quota tools differ in a number of ways to their IRIX counterparts
• Linux XFS does not support realtime subvolumes or Guaranteed-Rate I/O (GRIO).
• The mkfs command in Linux XFS uses the Version 2 directory format by default.
• Linux XFS supports mounting by label and mounting by uuid.
• The xlv volume manager is not available with Linux XFS. Volume support in Linux XFS is through standard Linux volume managers lvm and md.