Veritas File System 5.1 SP1 Administrator"s Guide (5900-1499, April 2011)

Mounting a VxFS file system
In addition to the standard mount mode (delaylog mode), Veritas File System
(VxFS) provides the following modes of operation:
■ log
■ delaylog
■ tmplog
■ logsize
■ nodatainlog
■ blkclear
■ mincache
■ convosync
■ ioerror
■ largefiles|nolargefiles
■ cio
■ mntlock|mntunlock
■ tranflush
Caching behavior can be altered with the mincache option, and the behavior of
O_SYNC and D_SYNC writes can be altered with the convosync option.
See the fcntl(2) manual page.
The delaylog and tmplog modes can significantly improve performance. The
improvement over log mode is typically about 15 to 20 percent with delaylog;
with tmplog, the improvement is even higher. Performance improvement varies,
depending on the operations being performed and the workload. Read/write
intensive loads should show less improvement, while file system structure
intensive loads, such as mkdir, create, and rename, may show over 100 percent
improvement. The best way to select a mode is to test representative system loads
against the logging modes and compare the performance results.
Most of the modes can be used in combination. For example, a desktop machine
might use both the blkclear and mincache=closesync modes.
The mount command automatically runs the VxFS fsck command to clean up the
intent log if the mount command detects a dirty log in the file system. This
functionality is only supported on file systems mounted on a Veritas Volume
Manager (VxVM) volume.
35VxFS performance: creating, mounting, and tuning file systems
Mounting a VxFS file system