Hi Alex,
After seeing some of your other messages, I guess you have this figured out, but let me briefly answer your questions, so maybe it can be useful for others as well (some of this applies only to R2 release):
First of all, there is no job-level process and task-level process. Everything, that is running is a separate task. However, application running as a task within the job can be aware of it and can access job/task properties by using scheduler APIs.
To connect to scheduler and obtain job object you need scheduler's hostname and job's ID. These are provided to the task via environment variables: CCP_SCHEDULER, CCP_JOBID.
Now having a first task of a job as a 'manager', which connects to the scheduler and opens its job object you can:
For Q1: If the hanging process causes task to fail, you can detect this by subscribing for ISchedulerJob.OnTaskState events.
For Q2: You can use ISchedulerJob.Progress and ProgressMessage properties to report overall job's progress based on the communication between 'manager' task and other tasks within the job. Progress and message will be visible in JobManager GUI and via CLI/Powershell
tools.
For Q3. You can use ISchedulerJob.SubmitTask(s) to create new tasks within the job.
I hope this information will be useful. Please let me know if you have any questions.
Best regards,
Łukasz
Lukaz,
I appreciate your help, yet I want to clarify a few things.
First of all, tasks in our system vary significantly in their run time. Some tasks may take minutes, while others may take a day. Hence subscribing to ISchedulerJob.OnTaskState events would not help here - there is no constant time interval which would indicate
non-responsiveness of a task (we can't estimate how much time it should take for a task to finish).
Then, I was indeed asking about progress, but, I insist, on the task level. I mean something like ISchedulerJob.Progress and ProgressMessage properties of a task, so progress of each task could be inspected. I understand this feature has not yet been implemented,
and that's why I was asking about a communication link between a task in a job and a job (let it be a "manager task"), so each task could report its progress separately to the manager.
Regarding ISchedulerJob.SubmitTask(s) - yes, this is what we're using now. I was hoping there is a way to eliminate communication overhead and send application-specific requests to the manager (e.g. create 1000 tasks of type X, rather than 1000 requests
to create one task of type X). Yet I see that the performance of task submission is reasonable, so this method is acceptable.
In a perfect situation, we'd like a task to be able to modify its custom properties while it's running, and this change would raise an event in the manager task, so it would be able to retrieve the updated properties. I understand this is not implemented,
so I'm looking for a workaround. Does it mean we will have to implement our own communication line via TCP/IP between the tasks and the manager task for these needs?
Thank you and I hope I made our requirements clearer.
Thanks again,
Alex.
