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From: pooja_at_[hidden]
Date: 2007-04-03 09:07:12


Hi,

Actually I am working on the course project in which I am running a huge
computational intensive code.
I am running this code on cluster.
Now my work is to find out when does the process send control messages
(e.g. compute process to I/O process indicating I/O data is ready)
and when does they send actual data (e.g I/O nodes fetching actual data
that is to be transfered.)
And I have to log the timing and duration in other file.

For this I need to know the States of Open MPi (Control messges)
So that I can simply put print statements in Open MPi code and find out
how it works.
For this reason I was asking to know the state changes or atleast the way
to find it out.
Also my proff asked me to look into BTl transport layer to be used with
MPi Api.

I hope you will help.

Thanks and Regards
Pooja

> On Apr 1, 2007, at 3:12 PM, Ralph Castain wrote:
>
>> I can't help you with the BTL question. On the others:
>
> Yes, you can "sorta" call BTL's directly from application programs
> (are you trying to use MPI alongside other communication libraries,
> and using the BTL components as a sample?), but there are issues
> involved with this.
>
> First, you need to install Open MPI with all the development
> headers. Open MPI normally only installs "mpi.h" and a small number
> of other heads; installing *all* the headers will allow you to write
> applications that use OMPI's internal headers (such as btl.h) while
> developing outside of the Open MPI source tree.
>
> Second, you probably won't want to access the BTL's directly. To
> make this make sense, here's how the code is organized (even if the
> specific call sequence is not exactly this layered for performance/
> optimization reasons):
>
> MPI layer (e.g., MPI_SEND)
> -> PML
> -> BML
> -> BTL
>
> You have two choices:
>
> 1. Go through the PML instead (this is what we do in the MPI
> collectives, for example) -- but this imposes MPI semantics on
> sending and receiving, which assumedly you are trying to avoid.
> Check out ompi/mca/pml/pml.h.
>
> 2. Go through the BML instead -- the BTL Management Layer. This is
> essentially a multiplexor for all the BTLs that have been
> instantiated. I'm guessing that this is what you want to do
> (remember that OMPI has true multi-device support; using the BML and
> multiple BTLs is one of the ways that we do this). Have a look at
> ompi/mca/bml/bml.h for the interface.
>
> There is also currently no mechanism to get the BML and BTL pointers
> that were instantiated by the PML. However, if you're just doing
> proof-of-concept code, you can extract these directly from the MPI
> layer's global variables to see how this stuff works.
>
> To have full interoperability of the underlying BTLs and between
> multiple upper-layer communication libraries (e.g., between OMPI and
> something else) is something that we have talked about a little, but
> have not done much work on.
>
> To see the BTL interface (just for completeness), see ompi/mca/btl/
> btl.h.
>
> You can probably see the pattern here... In all of Open MPI's
> frameworks, the public interface is in <level>/mca/<framework>/
> <framework>.h, where <level> is one of opal, orte, or ompi, and
> <framework> is the name of the framework.
>
>> 1. states are reported via the orte/mca/smr framework. You will see
>> the
>> states listed in orte/mca/smr/smr_types.h. We track both process
>> and job
>> states. Hopefully, the state names will be somewhat self-
>> explanatory and
>> indicative of the order in which they are traversed. The job states
>> are set
>> when *all* of the processes in the job reach the corresponding state.
>
> Note that these are very coarse-grained process-level states (e.g.,
> is a given process running or not?). It's not clear what kind of
> states you were asking about -- the Open MPI code base has many
> internal state machines for various message passing and other
> mechanisms.
>
> What information are you looking for, specifically?
>
>> 2. I'm not sure what you mean by mapping MPI processes to "physical"
>> processes, but I assume you mean how do we assign MPI ranks to
>> processes on
>> specific nodes. You will find that done in the orte/mca/rmaps
>> framework. We
>> currently only have one component in that framework - the round-robin
>> implementation - that maps either by slot or by node, as indicated
>> by the
>> user. That code is fairly heavily commented, so you hopefully can
>> understand
>> what it is doing.
>>
>> Hope that helps!
>> Ralph
>>
>>
>> On 4/1/07 1:32 PM, "pooja_at_[hidden]" <pooja_at_[hidden]> wrote:
>>
>>> Hi
>>> I am Pooja and I am working on a course project which requires me
>>> -> to track the internal state changes of MPI and need me to
>>> figure out
>>> how does ORTE maps MPi Process to actual physical processes
>>> ->Also I need to find way to get BTL transports work directly with
>>> MPI
>>> level calls.
>>> I just want to know is this posible and if yes what procedure I
>>> should
>>> follow or I should look into which files (for change).
>>>
>>>
>>> Please Help
>>>
>>> Thanks and Regards
>>> Pooja
>>>
>>> _______________________________________________
>>> devel mailing list
>>> devel_at_[hidden]
>>> http://www.open-mpi.org/mailman/listinfo.cgi/devel
>>
>>
>> _______________________________________________
>> devel mailing list
>> devel_at_[hidden]
>> http://www.open-mpi.org/mailman/listinfo.cgi/devel
>
>
> --
> Jeff Squyres
> Cisco Systems
>
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