I am using the parallel data structures in my .NET 4 application and I have a ConcurrentQueue that gets added to while I am processing through it.

I want to do something like:

personqueue.AsParallel().WithDegreeOfParallelism(20).ForAll(i => ... );

as I make database calls to save the data, so I am limiting the number of concurrent threads.

But, I expect that the ForAll isn't going to dequeue, and I am concerned about just doing

ForAll(i => {
    personqueue.personqueue.TryDequeue(...);
    ...
});

as there is no guarantee that I am popping off the correct one.

So, how can I iterate through the collection and dequeue, in a parallel fashion.

Or, would it be better to use PLINQ to do this processing, in parallel?