Charm++ parallel programming system

["Kale, Laxmikant V" <kale AT cs.uiuc.edu>]

Gengbin, Isaac: can he use the CCS interface for this? It is meant for 
external entities to inject messages into Charm++ computations, which is 
roughly what is happening here-- at least from the invocation point of view.

Sanjay

--
Laxmikant Kale                  http://charm.cs.uiuc.edu
Professor, Computer Science     
kale AT illinois.edu
201 N. Goodwin Avenue           Ph:  (217) 244-0094
Urbana, IL  61801-2302          FAX: (217) 265-6582



> -----Original Message-----
> From: Christian Perez 
> [mailto:christian.perez AT inria.fr]
> Sent: Friday, June 04, 2010 11:10 AM
> To: Kale, Laxmikant V
> Cc: 
> charm AT cs.uiuc.edu;
>  
> kale AT illinois.edu
> Subject: Re: [charm] Charm++ & thread in library ?
> 
> I was guessing it is not an intended usage. I am going to try an hack
> in
> my code not to invoke
> charm operations from those threads. It it fails, I will try another
> very very ugly hack but should work
> to remove those pthread calls.
> 
> I'll keep you inform.
> 
> Christian
> 
> On 06/04/2010 04:16 PM, Kale, Laxmikant V wrote:
> > This is not an intended usage, because Charm++ likes to assume
> control of cpus (and a pthread_created will relinquish that control..
> charm creates exactly the number of pthreads as the number of cores (or
> SMTs in some cases) on each node.
> >
> > When you create a new pthread, its going to create ambiguity about
> what the sending "PE" is, for Charm++. Troubles may emanate from that.
> But in principle, I think this can be supported with appropriate
> limitations with some work: it's a question of whether to support such
> a model.  (e.g. think about multiple pthreads created in this fashion.
> What global variables can they access? How to ensure thread safety in
> messaging layer underneath?)
> >
> >
> > --
> > Laxmikant Kale                  http://charm.cs.uiuc.edu
> > Professor, Computer Science     
> > kale AT illinois.edu
> > 201 N. Goodwin Avenue           Ph:  (217) 244-0094
> > Urbana, IL  61801-2302          FAX: (217) 265-6582
> >
> >
> >
> >> -----Original Message-----
> >> From: 
> >> charm-bounces AT cs.uiuc.edu
> >>  
> >> [mailto:charm-bounces AT cs.uiuc.edu]
> On
> >> Behalf Of Christian Perez
> >> Sent: Friday, June 04, 2010 7:10 AM
> >> To: 
> >> charm AT cs.uiuc.edu
> >> Subject: [charm] Charm++&  thread in library ?
> >>
> >> Hello,
> >>
> >> I'd like to know whether there is a simple solution to the following
> >> situation:
> >> A charm application is using a library that creates threads
> >> (pthread_create).
> >> Those threads would like to invoke methods on charm objects.
> >>
> >> When I test it (cf attached file), it bugs. Is it possible to
> support
> >> such a situation or not?
> >>
> >> Ugly details: the library is a JVM, but it also fails with simple
> example
> >> as in the attached file.
> >>
> >> Thank you!
> >>
> >> Christian
> >>