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Message Posted: Fri, 27 Aug 2004 @ 22:14:44 GMT

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As I understand it, you are correct in that there is a difference between flow control and AWT exhaustion. AWT exhaustion refers to the situation when all available AWTs being employed and there is additional work to be done. Flow control, as I understand it, is a state that the node(s) enter into when it has more work to do than it can handle. I do not know all of the possible conditions that would precipitate entering a state of flow control, but the one I am most familiar with had to do with AWT exhaustion.

Each AWT has its own sending and receiving mailboxes. In terms of optimal usage, you would want all available AWTs working on a task and having some number of processing waiting in the queue to be processed. As long as the queue is not long and does not get "backed up", life is good. However, when the queue depth for AWTs get too long, the node(s) in question will go into flow control so as to allow existing work to get done.

At least that is how I understand it.

If you are consistently getting into flow control, AWTs are fully utilized, your system is very well tuned and managed, and your other system resources are under-utilized, then I would think that increasing AWTs would help. Of course, those are a lot of assumptions about your system.

I hope this helps.

Regards,

Thomas F. Stanek
APP Consulting, Inc.

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