Enable Asynchronous Disk I/O

Enable asynchronous disk I/O on Linux, IBM, and HP-UX.

SAP recommends that you do not use block devices as database devices on UNIX and Linux systems; a system failure may lead to loss of data integrity if you do so.

If you are using raw devices on a UNIX platform, you cannot:

Set the disk init...directio or dsync parameter to true
Set the sp_deviceattr...directio or dsync parameter to true

If either of these are set to true, SAP ASE returns a message similar to:

You cannot set directio option for raw device '/dev/raw/raw235' or You cannot set attribute dsync for raw device

Enabling Asynchronous Disk I/O on Linux
Enable asynchronous I/O on Linux.
Enabling Asynchronous Disk I/O on IBM AIX
On IBM AIX, enable asynchronous I/O by adjusting the kernel parameters, using the System Management Interface Tool (SMIT).
Enabling Asynchronous Disk I/O HP-UX
To improve I/O performance on character or raw and block devices, enable asynchronous I/O by installing the HP asynchronous I/O driver from SAM.
Enabling Asynchronous I/O for File System Devices
Enable asynchronous I/O for file system devices on HP-UX.
Enabling Asynchronous I/O for File Systems
Enable asynchronous I/O for file systems on HP-UX.

Parent topic: Configure the Operating System