Before
SAS/IntrNet
9.2, a long-running job would occupy an Application Server until the
job was completed. This prevented new jobs from using that Application
Server. Starting with
SAS/IntrNet 9.2, long-running jobs can run in
the background. This new capability releases an Application Server
from the pool of Application Servers so that the server can continue
to run on its own until the job has completed. Then, the server exits.
A new Application Server can be started in the pool service if it
is needed for another job.
Long-running jobs also would often exceed the time-outs
that are set for the Application Broker, Web server, and Application
Server. For example, the Web server typically has a default time-out
of 5 minutes. By running the Application Server in the background,
certain time-outs can be avoided, and the server can be set up to
allow the job to run as long as required. To allow the Application
Server to be run in background mode, use the ALLOW_BACKGROUND option.
See ALLOW_BACKGROUND for more information.Starting with
SAS/IntrNet 9.2, the
APPSRVSET Application
Server function has two parameters that are used together to force
an Application Server to run in the background. The BACKGROUND parameter
removes the Application Server from the pool service so that it can
run on its own. The DISCONNECT parameter releases the Application
Broker (and subsequently the Web browser) from the Application Server.
The Web browser does not have to wait for a job to complete. A message
could first be returned to the user indicating that the job is running
and where to find any output when it is finished. After the Application
Server is disconnected, no further text can be sent back to the Web
browser. The results are returned using e-mail or stored for subsequent
retrieval. The following code is an example of how to use APPSRVSET
to run a job in the background:
data _null_;
rc = appsrvset('background', 300);
file _webout;
put "<html><body>";
put "<h1>The job has been submitted to the server.</h1>";
put "</body></html>";
rc = appsrvset('disconnect');
run;
/* Long-running SAS code here */
You must use the Load
Manager
-background option to allow programs to request background processing.
The background jobs appear in the Load Manager status program under
the special service
$background.