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Subject: Re: [OMPI users] Spawning processes through MPI::Intracomm::Spawn_multiple
From: vipin kumar (vipinkumar41_at_[hidden])
Date: 2009-07-15 00:58:05


Hi Ralph,

Thanks a lot for your effort and giving us freedom to choose hosts
dynamically. I am really excited to see such great feature working in my
programs.

again thank you very much :)

Regards,
On Tue, Jul 14, 2009 at 8:11 PM, Ralph Castain <rhc_at_[hidden]> wrote:

> Hi Vipin
> I have added support for these features to the OMPI trunk repository. They
> are only accessible via MPI_Comm_spawn or MPI_Comm_spawn_multiple, specified
> as MPI Info keys "add-host" and "add-hostfile". Check the man pages for
> those functions to see how they are used.
>
> Quick summary: I add the hosts found in any add-host and add-hostfile
> specifications to the list of hosts known to mpirun, and then use the
> provided hosts to constrain the launch of the specified apps. So spawning an
> app of "foo" with an info key of "add-host mike" will result in foo being
> launched on mike, without mpirun having previous knowledge of "mike".
>
> You'll have to wait to try it, though, until another problem in comm_spawn
> on the trunk gets fixed - hopefully, real soon (someone is working on it).
>
> HTH
> Ralph
>
> On Jul 2, 2009, at 1:28 AM, vipin kumar wrote:
>
> Hi Ralph,
>
> To add few more points to my queries, as you said earlier "addhost" and
> "addhostfile" features will come soon. So can you please tell how we are
> going to use those features, will there be any API for that to calll from
> inside the program or we have to execute command to use those features.
>
> Thanks,
>
> Regards,
> On Thu, Jul 2, 2009 at 12:46 PM, vipin kumar <vipinkumar41_at_[hidden]>wrote:
>
>> Hi Ralph,
>>
>> I am thankful to your reply regarding the matter, however to carry forward
>> with my activities it would be of great help if I can know where
>> OpenMpi/mpirun holds the contents of "hostfile" so that I can dynamically
>> add/alter the values till such a feature is officially included in OpenMpi
>> in the form of "addhost" and "addhostfile".
>>
>> Thanks.
>>
>> Regards,
>>
>>
>> On Thu, Jul 2, 2009 at 12:23 PM, Ralph Castain <rhc_at_[hidden]> wrote:
>>
>>> At the moment, the answer is "no". :-/
>>> However, we do have a "ticket" in our plans to add a "addhost" and
>>> "addhostfile" capability to the system. I haven't implemented it yet because
>>> of other priorities and the fact that nobody has asked for it before now.
>>>
>>> Well...actually, people -did- ask for it a long time ago, but not for
>>> quite awhile now. ;-)
>>>
>>> Anyway, I can implement those features pretty easily. Could get to it in
>>> the next few days - otherwise, it will have to wait another week as I will
>>> be out.
>>>
>>> Either way, though, it would only be in the OMPI devel trunk until the
>>> next feature series (1.5) has its first release. Haven't set the date for
>>> that, though it will likely be this summer.
>>>
>>> Ralph
>>>
>>> On Jul 2, 2009, at 12:45 AM, vipin kumar wrote:
>>>
>>> Hi all,
>>>
>>> I got the solution but its not flexible. I have to provide two host files
>>> "chfile" and "dhfile". Contents of host files are as follows
>>>
>>> $ cat chfile
>>> #This file contains all slaves as well as master node
>>> localhost
>>> 200.40.70.193
>>>
>>> $cat dhfile
>>> #This file contains all slave nodes
>>> 200.40.70.193
>>>
>>> and the command line I am using is
>>>
>>> $ mpirun -np 1 -hostfile chfile launcher -hostfile dhfile
>>>
>>> but this is not what I want.
>>> I don't know in advance which and how many remote nodes can be there.
>>> Dynamically nodes may be added and requested to serve the master. So I am
>>> assuming that I have only local machine where I will invoke launcher
>>> program. When one remote node gets added launcher program will launch one
>>> "slave" in local machine and one "rslave" in remote machine.
>>>
>>> Is there any other way to do this.
>>>
>>> Thanks.
>>>
>>> Regards,
>>>
>>> On Mon, Jun 29, 2009 at 10:49 AM, vipin kumar <vipinkumar41_at_[hidden]>wrote:
>>>
>>>> Hi all,
>>>>
>>>> I am trying to spawn dynamically processes in remote as well as local
>>>> machine using MPI::Intracomm::Spawn_multiple. I am using MPI::Info object to
>>>> tell where to launch processes using "host" key and "<ip_address>" as its
>>>> value but but I am getting the error
>>>>
>>>>
>>>> --------------------------------------------------------------------------
>>>> There are no allocated resources for the application
>>>> slaveprocess
>>>> that match the requested mapping:
>>>>
>>>>
>>>> Verify that you have mapped the allocated resources properly using the
>>>> --host or --hostfile specification.
>>>>
>>>> --------------------------------------------------------------------------
>>>>
>>>> I tried with "<hostname>" too.
>>>> but its not working.
>>>>
>>>> It works fine if I give the value "localhost" to "host:" key. It
>>>> launches successfully processes in local machine.
>>>>
>>>> any help will be greatly appreciated.
>>>>
>>>> Regards,
>>>> --
>>>> Vipin K.
>>>> Research Engineer,
>>>> C-Dot, Bangalore, India
>>>>
>>>
>>>
>>>
>>> --
>>> Vipin K.
>>> Research Engineer,
>>> C-DOTB, India
>>> _______________________________________________
>>> users mailing list
>>> users_at_[hidden]
>>> http://www.open-mpi.org/mailman/listinfo.cgi/users
>>>
>>>
>>>
>>> _______________________________________________
>>> users mailing list
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>>>
>>
>>
>>
>> --
>> Vipin K.
>> Research Engineer,
>> C-DOTB, India
>>
>
>
>
> --
> Vipin K.
> Research Engineer,
> C-DOTB, India
> _______________________________________________
> users mailing list
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> http://www.open-mpi.org/mailman/listinfo.cgi/users
>
>
>
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-- 
Vipin K.
Research Engineer,
C-DOTB, India