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RE: Any2OneCallChannel deadlocking?

Title: RE: Any2OneCallChannel deadlocking?

Can you email me your complete code?  I've tried to put together your example by modifying the existing demo application, and although I'm not getting the error message (I'm maybe not waiting long enough), I am definetely not getting the correct number of responses printed to the screen, and the program doesn't terminate.  Not sure if it's deadlock, but I'll take a closer look.

-----Original Message-----
From: Mailing_List_Robot on behalf of Sachin Desai
Sent: Tue 20/05/2008 01:31
To: java-threads@xxxxxxxxxx
Subject: Any2OneCallChannel deadlocking?


I've modified the Any2OneCallChannel example that's part of 
jcsp-1.1rc3 where I've added multiple callers for the call channel; 
the example had one and I'm testing with 200. I've commented out all 
System.out.* statements and each one of my 200 callers executes 100 
calls in a tight loop.

My Any2OneMain main program looks like:

        A[] a = new A[200];
        for (int i = 0; i < 200; i++) {
                a[i] = new A(c, 100);

        new Parallel(
                new CSProcess[] {
                        new Parallel(a),
                        new B2(c, 200 * 100)

where 200 is the number of processes and 100 is the number of calls 
each process makes. The run() method in class B1 looks like:

        for (int i = 0; i < count; i++) {

where count = 200 * 100. I wanted the program to terminate at 
execution end and not wait to process.

When I run the program it seems to deadlock or at least seems to hang 
for a long period of time. There are times when it completes but for 
the most part it hangs. Forcing the JVM to dump the stack trace, I see 
many instances of the following, I presume one for each running thread

"org.jcsp.lang.Parallel@31f26605" daemon prio=5 tid=0x000000010185b000 
nid=0x110651000 waiting for monitor entry 
   java.lang.Thread.State: BLOCKED (on object monitor)
        at org.jcsp.lang.Any2OneImpl.write(Unknown Source)
        - waiting to lock <0x00000001050d3f60> (a java.lang.Object)
        at org.jcsp.lang.Any2OneCallChannel.join(Unknown Source)
        at org.jcsp.demos.call.A.run(A.java:49)
        at org.jcsp.lang.Parallel.run(Unknown Source)
        at org.jcsp.lang.ParThread.run(Unknown Source)

My question is, is this a deadlock I'm seeing? Am I using the 
Any2OneCallChannel correctly? If not, what's the right way. What I'm 
trying to accomplish is having multiple callers call on a single 

I'm running this on a MacBook Pro 2.6GHz 4GB of memory.

Any help or pointers would be appreciated.

-- Sachin.


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