Veritas Quick I/O is a VxFS feature included in Veritas InfoScale Storage Foundation Standard and Enterprise products that enables applications access preallocated VxFS files as raw character devices. Quick I/O provides the administrative benefits of running databases on file systems without the typically associated degradation in performance.

Using Quick I/O is recommended on DB2 databases prior to DB2 8.1 with FixPak 4. With DB2 8.1 with FixPak 4 or later, you can use the Veritas Concurrent I/O feature, which provides high-speed access for SMS tablespaces as well as DMS tablespaces.

See About Concurrent I/O.