5. File System / Storage Management

Red Hat Enterprise Linux 5.7 provides the following notable file system improvements:
  • A new debugging facility for Network File System (NFS) address space operations (aops)
  • Additional checks to ensure that quota limits cannot be set too high.

5.1. Global File System 2 (GFS2)

The Red Hat GFS2 file system is a native file system that interfaces directly with the Linux kernel file system interface (VFS layer). When implemented as a cluster file system, GFS2 employs distributed metadata and multiple journals.
GFS2 in Red Hat Enterprise Linux includes the following notable new features:
  • The fallocate() system call preallocates file system blocks to a file. Red Hat Enterprise Linux 5.7 introduces support for the fallocate() system call on the GFS2 file system.
  • Performance when bouncing locks in a cluster with GFS2 is improved.
  • gfs2_grow is used to expand the GFS2 file system. Previously, growing a GFS2 file system, that was at full capacity, was unsupported. Red Hat Enterprise Linux 5.7 introduces support for growing a full GFS2 file system.

5.2. The XFS File System

XFS is a highly scalable, high-performance file system which was originally designed at Silicon Graphics, Inc. It was created to support extremely large file systems (up to 16 exabytes), files (8 exabytes) and directory structures (tens of millions of entries).
Usage of XFS in conjunction with Red Hat Enterprise Linux 5.7 High Availability Add-On/Clustering as a file system resource is now fully supported.