Subject: Re: [Fwd: [saga-rg] monitoring, again...]

[Andre Merzky]

Quoting [Raul Sirvent] (Nov 09 2005):
>> Ah, I am having a Deja Vu here :-)  I found in one of our
>> earlier discussions:
> 
> You mean we are always talking about the same thing? That's not good... :)

Right you are!  How is wether in Barcelona :-P?  

(Hehe, now that I am in Louisiana for a while, and don't
have to suffer from the rainy Dutch Fall I actually dare to
ask :-P)


> Yes. It is clear now. You support a threaded model with asynchronous 
> notifications, and you don't support a non-threaded model with 
> synchronous notifications. I'm just a bit worried about the CPU wasted 
> with active waits (to receive callbacks) in the main thread, or even 
> having to insert sleeps (as you do) in the code. Do you think it is 
> really so difficult to support both? (as Globus does, for instance).

difficult not:

 void event_poll 
 {
   while ( ! event_counter )
   {
     // that noeeds virtually NO CPU
     nanosleep (10); 
   }
 }

The internal callback mechanism would then increase
event_counter before any callback is issued.

The question with that really is:

 - do you want to wait for specific types of events
   -> how are types specified?
 - do you want to wait for events from any task?
   -> what object has the event_poll method?

Cheers, Andre.


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