[fpc-devel] Parallel Computing

[petr.kristan at epos.cz]

On Tue, Nov 04, 2008 at 10:08:09AM +0100, Michael Schnell wrote:
>
>> Michael. How many MT programs you really made?
>>   
> I don't know what you exactly mean here.
>
> If MT just stands for Multi-Threading. Lots of them as well in Pascal 
> (usually Delphi) as in GNU C. Multi-Processing or Calculation speed never 
> was an issue but providing low latency to some of the tasks (GUI serial and 
> TCP/IP communication tasks, you name it).
>
> As I already said, I never used OpenMP or similar tools but just TThread 
> (in Pascal) or my own stuff (in C).

My question was only for thought-provoking. Every programer which works with
threads, knows that is necessary give attention many things -- shared
memory, locking, deadlocks, race conditions, only thread safe calls...

I think that some keyword _parallel_ cannot solve this. In the hand of 
unexperienced programer brings more problems than profit.

_parallel_ can be maybe used for lightweight threads. But here we must keep in mind that 
thread creation is quite expensive. Depending on memory architecture,
number of CPUs and selected number of threads we can get different speedup or
slowdown too. 

Petr

-- 
Ing. Petr Kristan
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