[PD-dev] per-thread storage in Pd in support of pdlib - discussion?

[Mathieu Bouchard]

Le 2012-02-14 à 11:14:00, Charles Henry a écrit :

> On 2/13/12, Mathieu Bouchard <matju at artengine.ca> wrote:
>> Do you understand what I say, or you just repeat what I was replying to ?
>
> I thought I understood--was there something I missed?

I wouldn't have known that from your reply. It seemed to just continue 
where you had left. When I want to just add more to something I said, I 
just reply to my own mail. I don't quote someone's mail to say something 
completely unrelated to the quote.

> The point of the original remark is that you always lose some of your 
> potential computing power when trying to use multiple resources.

Part of the computing power has to be put on communication and 
coordination, which are essential parts of collaboration. It doesn't 
necessarily mean that those ressources could have been used for anything 
else. If you measure a programme's computing time without counting its 
I/O, it'll appear more efficient than if you counted the I/O. For 
multi-processor computing involving divide-and-conquer or pipelining, some 
of the work internal to the algorithm is I/O and you can't avoid measuring 
it. This might skew perception a bit.

> You contrast with the capability of parallel computing to accomplish a 
> certain amount of work in less time.  I don't want to argue with 
> you--these are just the two sides of the coin.

Yes, I was stating the other side, because there hadn't been any 
clarifications on what « the sum » and « the parts » ought to be in that 
case. People compare total amounts of gigaflops because they can, and 
because it's fairly simple to measure a score to determine a winner, 
which leads to competitions that take a lot of time and effort. This 
orients a lot of the default thinking about what is « the » goal of 
parallelism.

> I had actually typed out and then deleted some more things

I also do that a lot. If I had kept them, I could make a book out of them, 
and store it in a random position in the Library of Babel.

> about a successful project that accelerated computing time from weeks to 
> hours, but I thought they were boring.

If you want to post it, post it, and if you don't want to, don't.

  ______________________________________________________________________
| Mathieu BOUCHARD ----- téléphone : +1.514.383.3801 ----- Montréal, QC