HP-UX 11i June 2003 Release Notes

New and Changed Disk and File Management Features
New Version of Journaled File System (JFS)
Chapter 11
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New Version of Journaled File System (JFS)
new at 11i
original release
HP-UX 11i includes a new version of the Journaled File System (JFS): version 3.3, as
opposed to the previous version 3.1. (JFS is also known as the VERITAS File System or
VxFS).
New features in JFS 3.3 include the following:
• support for access control lists (ACLs), the only HFS feature unavailable in JFS 3.1
(see aclv (5), getacl (1), setacl (1), acl (2), and aclsort (3C)).
• a new disk layout (that is, version 4)
• a new command for tuning a VxFS file system: vxtunefs (see vxtunefs (1M) and
tunefstab (4))
• a new command, vxfsconvert, for converting an HFS file system to a JFS file
system. This command also converts HFS ACLs to JFS ACLs, with some limitations
(see vxfsconvert (1M)).
• performance enhancements
• new packaging and licensing strategy for HP OnLineJFS 3.3 (see vxlicense (1M) and
vxenablef (1M))
• a better solution for the file system shrink limitation when using the version 4 disk
layout
With the HP-UX 11i release, JFS becomes a superset of the functionality available in
HFS now that JFS includes support for ACLs. This enables all users to consider
migration from HFS to JFS.
In HP-UX 11i, one kernel library contains the kernel functionality for both the JFS and
the OnLineJFS products. When you install the JFS product, all the software for
OnLineJFS is also installed, but its features are not enabled unless you also purchase it.
Having all the kernel functionality for both products in one library resolves many of the
patching problems that existed in previous releases.
With the JFS version 4 disk layout in JFS 3.3, you are much less likely to encounter the
file system shrink limitation that existed in earlier JFS versions in HP-UX 10.20 and
11.0. In other words, JFS previously could not shrink a file system if there were file
extents residing in the area being reduced. Now, JFS 3.3 (with the version 4 disk layout)
will attempt to move extents off the area of the file system being reduced. This provides
a greater chance of success when shrinking JFS file systems. However, there may still be
some occasions where JFS cannot move extents off the area of the file system being
reduced, in which case a shrink will still fail.