Summary information |
|
|---|---|
Default value |
0 |
Valid values |
1 (enabled), 0 (disabled) |
Status |
Static |
Display level |
Comprehensive |
Required role |
System administrator |
Configuration group |
Disk I/O |
Setting enable hp posix async i/o to 1 enables asynchronous I/O on database devices created on on HP-UX 11.31 and later file systems. You must first enable Adaptive Server to use asynchronous I/O with the allow sql server async i/o configuration parameter.
The combination of these configuration parameters determines whether Adaptive Server uses asynchronous or synchronous I/O for raw partitions and file systems:
enable hp posix async i/o |
allow sql server async i/o = 0 |
allow sql server async i/o = 1 |
|---|---|---|
Set to 0 |
Synchronous I/O for file systems Synchronous I/O for raw devices |
Synchronous I/O for file systems Uses /dev/async asynchronous I/O for raw devices |
Set to 1 |
Synchronous I/O for file systems Synchronous I/O for raw devices |
POSIX asynchronous I/O for file systems POSIX asynchronous I/O for raw devices |
enable hp posix async i/o improves
performance when you allocate database devices on file systems,
but may decrease performance on database devices that are allocated
on raw devices.
