Re: basic question on Ada tasks and running on different cores

[Shark8 <onewingedshark@gmail.com>]

On Tuesday, May 15, 2012 1:55:01 AM UTC-5, Randy Brukardt wrote:
>
> clearly, there are 
> many applications where the performance isn't that critical or even where 
> the added cost might actually provide some speed-up.

Indeed, though this is really just the recapitulation of the themes "work smarter, not harder". If we might draw a parallel, this is to parallelism what basic-techniques were to data-structures (ie the very early days of CS).

Someday somebody realized, "if I sort things in this list, then finding them will be faster" and so we got all sorts of sort-algorithms and studies on the properties thereof and the like.

And that's where we're at WRT parallelism; we've got people looking into everything from instruction-level to task/program-level and trying to figure out the best way to do things. (But here the problem's more difficult; because, in addition to the amount of parallelization, the different granularities interact with the evaluation-metrics, and we're only just beginning to see to what extent.)

But, in the end, I think you're right: intuitively the fine-grained should have a disadvantage because there will likely be more overhead cost due to the synchronization/data-payload ratio. {We may be wrong though, sometimes intuition leads astray; and even slight improvements in such fields may lead to better compilers and/or OSes.}