The directio parameter for disk init, disk reinit, and sp_deviceattr lets you configure Adaptive Server to transfer data directly to disk, bypassing the operating system buffer cache. directio performs I/O in the same manner as raw devices and provides the same performance benefit, but has the ease of use and manageability of file system devices.
By default, the directio option is set to false (off) for all platforms.
For more information on using directio, see the System Administration Guide, Volume 1.