Re: ATC---The Holy Grail of Ada Tasking?

[franke@paxp12.mipool.uni-jena.de (Frank Ecke)]

On 8 Jul 1998 21:00:03 -0400, Robert Dewar <dewar@merv.cs.nyu.edu> wrote:

>
> I must say that referring to the ATC abomination as the holy grail of
> Ada tasking seems almost sacriligeous. To me this is one of the worst
> features of Ada 95. It introduces significant distributed overhead,
> and the burden of making your code abort safe (especially when there
> is no way, if you are not using pramga Abort_Defer, a special GNAT
> pragma) to conveniently make code abort safe, except encapsulating it
> in junk protected records, is FAR too heavy. We have had a few people
> try to use ATC extensively, but in most cases they gave up (making
> code async abort safe is really a VERY difficult discipline). Unless
> you are very careful ATC is asking for non-repeatable troubles in
> complex programs.
>


I agree; ATC is a subtle topic and I did not intend to praise it.
Actually, the phrase ``Holy Grail of Ada Tasking'' was meant ironically in 
the sense of ``if you want to live in bliss with Ada Tasking, don't touch that
stuff!''  Sorry for introducing this ambiguity!

   The point is that I am currently writing a project alfa core in which I am
investigating and comparing the concurrency features of Ada, CHILL, and Java.
This, however, requires me to scrutinize each and every aspect of concurrency
in these languages.


Frank