Blogs

DataRush is sufficiently sophisticated (or at least different) that understanding it takes several passes. I am writing a series of posts aimed toward exploring what DataRush is and is not. This should give the passing programmer a better feel for what DataRush might do for them and how it fits into the broader scheme of concurrent programming techniques.

So, back to the question at hand; is DataRush dataflow? The answer is obvious: that depends upon what "dataflow" is.

According to [CTMCP], dataflow behavior results when expressions contain unbound variables. When execution reaches such an expression, the program simply pauses, awaiting a value. If at some point in the future another thread binds a value to the variable, the program picks up where it left off. They call variables with these characteristics dataflow variables. A simple example in Oz (from page 60) follows:

local X Y Z in
  X=10
  if X>=Y then Z=X else Z=Y end
end

Note that X is declared, then immediately bound to a value. The purpose of the expression is to bind Z. However, that leaves Y unbound. From the expression above, we simply cannot tell what value Y should take and, unlike some other programming languages, Oz does not arbitrarily specify a default value.

I just got back from an HP show where I had some interesting conversations regarding the crisis that hasn't seemed to have happened yet.

The key to the Sherlock Holmes mystery, "The Hound of the Baskervilles" was this: Why the dog didn't bark?

At a recent industry conference, it was shown that the biggest growth area in computing is HPC, or High Performance Computing. This was surprising, even to those in this field, as it has historically been a fairly small, insular, academic area populated by geeky professors and hard-working grad students, all using Fortran.

The first time I blogged on this, Explaining our secret sauce, I referenced the Wikipedia entry for "dataflow programming".

Before our current crop of graduates were born, there was the movie "The Graduate". One famous scene has our hero walking around at a party in his honor. He is given some sage career advice: "One word. Plastics".