topic Re: Synchronization puzzle in Alfresco Archive

Synchronization puzzle

fritz128 — Thu, 03 Oct 2013 14:37:39 GMT

To understand why I decide to use a semaphore for async process launching You should use the whole post In other case you can read only question section.Question:Can I synchronously launch asynchronous subprocess? I mean (see code below), if I release semaphore inside a asynchronous subprocess, can

Re: Synchronization puzzle

trademak — Thu, 03 Oct 2013 19:09:57 GMT

I don't think I understand it yet. If you want each sub process to have it's own scope of variables I would recommend to use a call activity. Is than an option for you?

Best regards,

Re: Synchronization puzzle

fritz128 — Thu, 03 Oct 2013 21:12:38 GMT

As I understand I can't simultaneously launch multiple async callActivities from one user task.
Question1 Can I?

main point
And another question. I've already written a demo with the same Activiti/Spring configurations, the same workflow and the same way to call asynchronous subprocesses. And it works! But the same doesn't work in my application!
I debuged it and it appeares that in my app after signalEventReceived doesn't invoke next method of java.lang.Thread class. In my demo where all works fine it the proceeding of new async subprocess begins from those method.:
<java>
@Override
    public void run() {
        if (target != null) {
            target.run();
        }
    }
</java>
Question2
How does signalEventReceived works. Does it directly invoke Thread.run method??

Re: Synchronization puzzle

jbarrez — Fri, 04 Oct 2013 08:33:26 GMT

signavlEventReceived uses the current thread, ie the thread which calls that method.

In case of async, it will hand it over to the job executor. Is the job executor running?

Re: Synchronization puzzle

fritz128 — Fri, 04 Oct 2013 10:39:44 GMT

How can I check if the JobExecutor is running?
I've set the next option property name="jobExecutorActivate" value="true"
As I mentioned above, in case when it doesn't work it doesn't invole Thread.run and ExecuteJobRunnable.run methods!

What is VERY STRANGE:
I've the same code in two places of my application: in first it works, in the second it doesn't!

The first (works fine):
<java>
runMainProcess();
for (int i = 0; i < 10; i++) {
SemaphoreWrapper.acquire();
runtimeService.signalEventReceived("signal", executionId);
}
</java>

But if to move for-loop and runMainProcess() to two different requests it DOESN'T work. I've checked in debug: executionId, commandExecutor and all other parameters are the same!

In which cases Activiti doesn't run new async subprocess before next cycle of for-loop?

Re: Synchronization puzzle

jbarrez — Mon, 21 Oct 2013 09:55:12 GMT

That sounds very very weird … can't really explain why the exact code does two different things dependending on the setup.