Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

Enabling Concurrent I/O for Sybase
Because you do not need to extend name spaces and present the files as devices,
you can enable Concurrent I/O on regular files.
Before enabling Concurrent I/O, review the following:
■ To use the Concurrent I/O feature, the file system must be a VxFS
file system.
■ Make sure the mount point on which you plan to mount the file
system exists.
■ Make sure the DBA can access the mount point.
Prerequisites
To enable Concurrent I/O on a file system using mount with the -o cio option
◆
Mount the file system using the mount command as follows:
# /usr/sbin/mount -F vxfs -o cio special /mount_point
where:
■ special is a block special device.
■ /mount_point is the directory where the file system will be mounted.
For example for Sybase, to mount a file system named /datavolon a mount point
named /sybasedata:
# /usr/sbin/mount -F vxfs -o cio /dev/vx/dsk/sybasedg/datavol \
/sybasedata
The following is an example of mounting a directory (where the new SMS
containers are located) to use Concurrent I/O.
To mount an SMS container named /container1 on a mount point named /mysms:
# /usr/sbin/mount -Vt namefs -o cio /datavol/mysms/container1 /mysms
Disabling Concurrent I/O for Sybase
If you need to disable Concurrent I/O, unmount the VxFS file system and mount
it again without the mount option.
105Improving database performance with Veritas Concurrent I/O
Enabling and disabling Concurrent I/O