For devices that are initialized on UNIX operating system files, choose one of these methods to ensure that writes on the device occur directly on the physical media:
Use the directio parameter with disk init, disk reinit or sp_deviceattr
Specify the dsync setting with disk init
directio and dsync parameters are mutually exclusive. If a device has dsync set to true, you cannot set directio to true for this device. To enable directio for a device, also reset dsync to false.
