Thread: What is task start time and task end time?

When you monitor your workload that ran on a particular session, you can see task start time and task end time as shown in the picture below. It is good to know the exact definition of those times in order to better understand the performance of your real-time Symphony application.


Note that both times are from the perspective of SSM.

1. Starting time is the time that the SSM dispatches the task to a *SIM*.
2. Ending time is the time that the SSM receives and processes the task result (SSM has to minimal processing to figure out whether the task is really done, or whether it need to be retried).

Young, I see a "Reran" Column to the right of "Ended". When and how does a Task "rerun" ?

Hi ComputerGuy!

1. In case of SSM failover or restart, tasks must rerun if the session is configured to be not recoverable.
2. If SIM is in failure recovery process, SSM reques and reruns tasks for the session that was running on SIM.

You can specify that if a task fails it should be rerun by specifying the taskRetryLimit attribute in the application profile (in SessionType section). This informs Symphony how many times it should rerun the task before giving up.

Young

Task can also be configured to "rerun" on scenarios such as Service Exit, Exception, Timeout, and Control Code.

Application error handling behavior is configured in Service->Control section of Application Profile. "Rerun" task is specified by the attribute actionOnWorkload="retry". For example:

<Method name="Invoke">
<Timeout duration="0" actionOnSI="restartService" actionOnWorkload="retry"/>
<Exit actionOnSI="restartService" actionOnWorkload="retry"/>
<Return controlCode="0" actionOnSI="keepAlive" actionOnWorkload="succeed"/>
<Exception type="failure" controlCode="0" actionOnSI="keepAlive" actionOnWorkload="retry"/>
<Exception type="fatal" controlCode="0" actionOnSI="keepAlive" actionOnWorkload="fail"/>
</Method>

For more information, refer to "Service error handling control" section of the Development Guide:

http://www.hpccommunity.org/exdata/soam/doc/SymDEKnowledgeCenter/development_sym/index.htm?service_error_handling_featureref.html~m ain

Thanks guys for answering. Documentation also very useful