| System Options under z/OS |
Specifies whether asynchronous I/O is enabled.
| Valid in: |
configuration file, SAS invocation
|
| Category: |
Files: External files
|
|
Files: SAS Files
|
| Restriction: |
The ASYNCHIO system option cannot be used
in a UNIX operating environment.
|
| PROC OPTIONS GROUP= |
EXTFILES
|
|
SASFILES
|
- ASYNCHIO
-
allows other logical SAS tasks to execute (if any are ready)
while the I/O is being done, which might improve system performance.
- NOASYNCHIO
-
causes I/O to wait for completion. This is the default.
The ASYNCHIO system option is the mirror alias of the
system option NOSYNCHIO. NOASYNCHIO is equivalent to SYNCHIO.
The
Base SAS engine and other engines are able to process several tasks concurrently.
For example, you can enter statements into the Program Editor at the same
time that PROC SORT is processing a large file. The reason that this is possible
is that the engine enables task switching.
Task switching is possible because the engine architecture supports
the ability to start one task before another task is finished, or to handle
work asynchronously. This ability provides greater efficiencies during processing
and often results in faster processing time. The ASYNCHIO system option controls
this activity.
Copyright © 2009 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
