Re: [wsbpel] Issue - 166 - Let's try it again

[<andrew.francis@mail.mcgill.ca>]

Hello Ron:

>The term "atomic" has been turned, by some,
> into a synonym  for ACID. This is incorrect. The term
> atomic simply means that changes  to the shared variables
> are made at once, indivisibly, or not at all.
> Consistency, isolation, and durability are separate
> concerns, and are  not required by the current
> specification. I believe Danny and Yaron  have
> illustrated this point well.

> Atomic assignment, by itself, leaves us with some open
> questions about concurrent behaviour. This is well
> >illustrated by the "concurrent  counter" example that>has been floated on this thread.

I think the concurrent behaviour argument is specious.
My simple approach to the problem is to ask myself the
question:

"Can a race condition occur on an atomic operation"?

"Atomic" by definition, denotes indivision. The answer
is "no": what is there to race to besides the single
instruction?  Would we be having the same argument
if it were say an assembly level test-and-set instruction
or an instruction that executed in one CPU clock cycle?


Cheers,
Andrew