Re: Gnat and priority level

["Alex R. Mosteo" <devnull@mailinator.com>]

mferracini wrote:
>>You can't (at least easily). Not only the gnat implementation uses
> 
> just
> 
>>32 priorities, but these are mapped to underlying windows priorities,
>>which are only 7, if I remember correctly (yes, there's overlapping).
> 
> 
> and with Linux rt version like RT-Linux there are the some problem?
> thanks again.

Take the following with a grain of salt, since I'm much less experienced 
with gnat for linux.

Firstly, I think that gnat doesn't target the RT capabilities of 
RT-Linux, so you'll really have regular non-RT linux threads. Unless 
someone has a patch for it.

Second, you can choose two threading implementations with gnat for linux:

* linux native threads, whose particularities I don't know but some 
linux expert could tell you (BTW, using the old 2.4 thread 
implementation, not the new 2.6 one).

* fsu-threads (I think) which if I remember correctly are 
POSIX-compliant or something-else-compliant which native linux's aren't. 
Those have the particularity that you have a single linux process, so a 
blocking call in any fsu-thread will block all the others (i.e. the 
linux thread is blocked).

Someone more experienced can confirm these things? I'm interested in the 
details too.