VERITAS File System 3.5 (HP OnlineJFS/JFS 3.5) Release Notes (5971-4774, August 2003)

VERITAS File System 3.5 (HP OnlineJFS/JFS 3.5) Release Notes
New and Changed Features
Chapter 1
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See the mkfs (1M) manual page for more information.
• VxFS System Activity Reporter
The vxfsstat command displays the VxFS file system statistics, which can be used
to analyze performance and to aid in tuning. Similar to the sar (1M) command,
vxfsstat gathers statistics on buffer cache, inode cache, and per-CPU usage.
See the vxfsstat (1M) manual page for detailed information.
• Forced Unmounts
A base/full VxFS 3.5-specific vxumount command has been introduced to perform
forced unmounts (vxumount -o force) of VxFS file systems. This is useful in a
variety of situations such as High Availability environments where a mounted file
system could prevent timely failover. Any active process with I/O operations pending
on an unmounted file system receives an I/O error (EIO).
IMPORTANT This command can cause data loss and must be used carefully.
See the vxumount (1M) manual page for more information.
• File Access Time Disabling
The -o noatime option was added to the mount command to disable access time
updates. This improves performance in read-only environments by eliminating
unneeded write operations.
• Parallel Log Replay
The fsck -o p option and fsck -P option allow a log replay on multiple file systems
in parallel. The parallel fsck functionality improves system start-up times.
• New VxFS Directory Name Lookup Cache (DNLC)
The new DNLC caches filenames less than or equal to 32 characters instead of 39
characters as in VxFS 3.3. The global variables ncsize and vx_ncsize have no
impact on the size of the VxFS 3.5 DNLC, which is sized by vxfs_ninode.
• New VxFS Buffer Cache for Meta-data Only
This buffer cache can be tuned with vx_bc_bufhw global tunable. The default size is
based on the memory size.
• Support for File Systems upto 4 Terabytes in Size
VxFS supports file systems upto 4 terabytes in size.
• New Version 5 Disk Layout
Version 5 enables the creation of file system sizes up to 4 terabytes. Files can be a
maximum of two terabytes. File systems larger than 2 TB must be created on a
VERITAS Volume Manager volume. Version 5 also enables setting up to 1024 access
control list (ACL) entries.