Re: GNAT and Tasklets

[vincent.diemunsch@gmail.com]

Le dimanche 14 décembre 2014 01:18:42 UTC+1, Hubert a écrit :

> the result of my research was that depending 
> on the OS the Ada program was running on you could get several 100 OS 
> threads or maybe 1-2K on Linux but there is an upper limit because every 
> OS thread that runs a task will have a stack associated with it, so 
> mostly the available memory is the limit, I think.
> [...]
> My solution was to implement my own pre-emptive Job system on top of the 
> OS threads. I allocate as many threads (or Tasks in Ada) as there are 
> processor cores and then assign a number of Jobs to each.
> [...]
> Depending on what your requirements are (great number of parallel Jobs), 
> this may very well be your only reliable solution.
> 

Yes, I think you are completely right. Is your library private or do you plan to release
it as Open Source ?

This shows clearly that the compiler wasn't able to produce an adequate solution, even 
if the case of a lot of little local tasks is quite simple, and has become a standard way of
using multicore computers (see for instance Grand Central Dispatch on Mac OS X). 

I really hope that Ada 202X will limit new features to a few real improvements, and try hard improving compilers.

Kind regards,

Vincent