> > I'm still looking for an answer to parallelizing a loop with common
> > data for each iteration.
>
> Sorry, things have been a little hectic and this must have slipped through
> the cracks.
>
> > It is my understanding that the value vC
> > would be private to each iteration of the ateach loop. This doesn't
> > seem to be the case. Output is below. I'm using version 1.7.7.
>
> vC is private, but the object it is pointing to is not.
>
> I believe in 1.7.7 Complex is an object,
I wrote my own class for this.
> so although each iteration has its
> own private pointer to C, they are still pointing to the same object.
> Therefore the updates from one iteration are visible in others because
> there is a single object that is being accessed by all the iterations.
>
> Does that make sense?
That makes sense, but obviously this is not what I want. Is there a simple way
in X10 to get a such an object to be privatized among the iterations? This code
snippet is an example of the code I'm working with. The actual code involves a
large data structure which needs to be unique to each iteration with no loop
carried dependences. Sequentially this is no problem. Concurrently, each
iteration needs a separate copy.
Any help is appreciated.
Jim
>
> >
> >
> > public class TestVal{
> > public static def main(args:Rail[String]){
> > var c: Complex = new Complex();
> > var reg: Region{rank==1} = [1..8];
> > var dist: Dist{rank==1} = Dist.make(reg);
> >
> > val vC = c;
> > finish ateach((i) in dist)
> > {
> > vC.imag = i as Double;
> > for ( var n: Int = 0; n < 100; n++ );
> > Console.OUT.println(vC);
> > }
> > }
> > }
> >
> >
> > Output: Notice the absence of (0,8) and the replication of (0,2). It
> > seems there is a data race on the vC, but my understanding is that
> > vC would be local to each thread.
> >
> > $ x10 TestVal
> > (0.0, 1.0)
> > (0.0, 7.0)
> > (0.0, 6.0)
> > (0.0, 5.0)
> > (0.0, 4.0)
> > (0.0, 3.0)
> > (0.0, 2.0)
> > (0.0, 2.0)
> >
> >
> > If I am misunderstanding this, can anyone offer a correction? In
> > this example, I want vC to be private (local) to each iteration.
> > I.e., each iteration gets its own copy.
> >
> > Thanks,
> >
> > Jim
>
>
>
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