HP Integrity NonStop H-Series User Manual
Page 195
Syntax:
-DSessionBasedLoadBalancing=[ true | false ]
NOTE:
The default value of
-DSessionBasedLoadBalancing
is set to
true
.
For example, if you want to enable the
SessionBasedLoadBalancing
feature for your
Axis2/Java application and save the application sessions in a persistent store, set the
Arglist
as:
Server $server_objectcode {
…
…
…
…
Arglist -DSessionBasedLoadBalancing=true \
-DSaveSessionOnCreation=true \
…
…
…
…
}
where,
server_objectcode
is mapped to the
servlet.ssc
object in the
<iTP WebServer
deployment directory>/bin
directory on OSS.
While setting these arguments, consider the following:
1.
If both the
SaveSessionOnCreation
and
SessionBasedLoadBalancing
options
are set to
false
, and if a Persistent Manager is configured with a persistent store, all
sessions are written to the store at the end of each request processing cycle. As a result,
all changes made to the session by the user application are persisted to the store.
2.
When
SessionBasedLoadBalancing
is set to
false
and a Persistent Manager is
configured with a persistent store, sessions are written to the store at the end of each
request processing cycle. As a result, all changes made to a session by the client
application are persisted to the store.
NOTE:
When the
SessionBasedLoadBalancing
feature is turned ON, messages
are delivered to NSJSP not only through TS/MP but also through file system calls. Hence,
there could be a situation that all messages delivered to a particular dynamic process
are through file system calls and none through TS/MP. Therefore, TS/MP may assume
that a particular dynamic process is not required any more and will shut down the
process. However, that dynamic process can have valid session objects in memory,
which will be lost if the process is shutdown. With the
SessionBasedLoadBalancing
feature turned ON, it is important not to configure dynamic processes.
Enabling or disabling the
SessionBasedLoadBalancing
feature depends on the
application requirement. Your Axis2/Java application might encounter any of the
following scenarios:
— The application depends heavily on the state stored in session objects. Therefore,
session objects cannot be lost and the application cannot recover from loss of state.
— Application response is of prime importance and the application can recover from
a loss of state.
— The application is expected to handle largely varying loads and having a large
number of static NSJSP instances is not an option.
— The session objects must be valid for large durations (such as an entire day).
— The session objects must be available whenever the application restarts.
NonStop Platform Configurations
195