[mpich-devel] MPIR_CVAR_CH3_RMA_GC_NUM_TESTED

[Hal Finkel]

----- Original Message -----
> From: "Xin Zhao" <xinzhao3 at illinois.edu>
> To: "Hal Finkel" <hfinkel at anl.gov>
> Cc: "Pavan Balaji" <balaji at anl.gov>, devel at mpich.org
> Sent: Monday, June 30, 2014 3:59:50 PM
> Subject: RE: MPIR_CVAR_CH3_RMA_GC_NUM_TESTED
> 
> Hi Hal,
> 
> The functions of poking progress engine are MPID_Progress_poke(),
> MPID_Progress_wait() and MPID_Progress_test(), but they are not
> provided with a request pointer directly.
> By saying "pass the single request pointer", I mean we pass it when
> issuing operations (location I mentioned in the last email), and if
> it is not completed, the request will be enqueued in a queue in the
> lower layer. When we call MPID_Progress_ functions, the progress
> engine will process on that queue and try to make more requests
> completed.

Thanks, now I understand what you meant.

 -Hal

> 
> Xin
> ________________________________________
> From: Hal Finkel [hfinkel at anl.gov]
> Sent: Monday, June 30, 2014 3:45 PM
> To: Zhao, Xin
> Cc: Pavan Balaji; devel at mpich.org
> Subject: Re: MPIR_CVAR_CH3_RMA_GC_NUM_TESTED
> 
> ----- Original Message -----
> > From: "Xin Zhao" <xinzhao3 at illinois.edu>
> > To: "Hal Finkel" <hfinkel at anl.gov>
> > Cc: "Pavan Balaji" <balaji at anl.gov>, devel at mpich.org
> > Sent: Monday, June 30, 2014 3:39:20 PM
> > Subject: RE: MPIR_CVAR_CH3_RMA_GC_NUM_TESTED
> >
> > Hi Hal,
> >
> > I am not sure if I understand you correctly. If you mean the
> > function
> > that CH3 uses to pass the message to the lower layer, it indeed
> > tests if it is completed or not upon return from nemesis. If
> > completed, CH3 will free that operation immediately, if not, it
> > will
> > leave that operation in the list. You can refer to L1087~L1097 in
> > src/mpid/ch3/src/ch3u_rma_sync.c in latest mpich/master about this.
> 
> No, I mean where is the code in the CH3 layer that calls the nemesis
> layer (pokes the progress engine?) providing it only with the single
> request pointer? In short, where is this "We didn't pass the list to
> the nemesis layer but only pass the single request pointer"?
> 
> Thanks again,
> Hal
> 
> >
> > Xin
> > ________________________________________
> > From: Hal Finkel [hfinkel at anl.gov]
> > Sent: Monday, June 30, 2014 3:07 PM
> > To: Zhao, Xin
> > Cc: Pavan Balaji; devel at mpich.org
> > Subject: Re: MPIR_CVAR_CH3_RMA_GC_NUM_TESTED
> >
> > ----- Original Message -----
> > > From: "Xin Zhao" <xinzhao3 at illinois.edu>
> > > To: "Hal Finkel" <hfinkel at anl.gov>, devel at mpich.org
> > > Cc: "Pavan Balaji" <balaji at anl.gov>
> > > Sent: Monday, June 30, 2014 2:14:15 PM
> > > Subject: RE: MPIR_CVAR_CH3_RMA_GC_NUM_TESTED
> > >
> > > Hi Hal,
> > >
> > > Currently the RMA operation list is implemented in CH3 layer,
> > > whereas
> > > the progress engine is implemented in nemesis layer. We didn't
> > > pass
> > > the list to the nemesis layer but only pass the single request
> > > pointer, so the progress engine now only modify on the request
> > > pointer.
> >
> > Thanks for the explanation. FWIW, I don't understand why the
> > calling
> > code (in CH3) could not test for complete upon return from nemesis
> > and handle it then. Which function handles this?
> >
> >  -Hal
> >
> > > This is one of the problems we have with the current
> > > separation of the CH3 and nemesis layers, we plan to merge these
> > > layers in future and this should be fixed at that time.
> > >
> > > Thanks,
> > > Xin
> > > ________________________________________
> > > From: Hal Finkel [hfinkel at anl.gov]
> > > Sent: Monday, June 30, 2014 1:28 PM
> > > To: devel at mpich.org
> > > Cc: Zhao, Xin; Pavan Balaji
> > > Subject: Re: MPIR_CVAR_CH3_RMA_GC_NUM_TESTED
> > >
> > > Xin, et al.,
> > >
> > > Regarding 283319f5d9d1cdbcf016dc0ff8ab284114c0be7e (which added
> > > MPIR_CVAR_CH3_RMA_GC_NUM_TESTED and associated code): If a
> > > request
> > > is completed by the progress engine, why can't the progress
> > > engine
> > > move it to the beginning of the list (or the end), and have
> > > rma_list_gc only search from the beginning (or end) until it
> > > finds
> > > an incomplete request?
> > >
> > > Thanks in advance,
> > > Hal
> > >
> > > --
> > > Hal Finkel
> > > Assistant Computational Scientist
> > > Leadership Computing Facility
> > > Argonne National Laboratory
> > >
> >
> > --
> > Hal Finkel
> > Assistant Computational Scientist
> > Leadership Computing Facility
> > Argonne National Laboratory
> >
> 
> --
> Hal Finkel
> Assistant Computational Scientist
> Leadership Computing Facility
> Argonne National Laboratory
> 

-- 
Hal Finkel
Assistant Computational Scientist
Leadership Computing Facility
Argonne National Laboratory