Sure:
$ ompi_info --param hwloc all -l 9
…..
MCA hwloc: parameter "hwloc_base_cpu_set" (current value: "",
data source: default, level: 9 dev/all, type:
string)
Comma-separated list of ranges specifying logical
cpus allocated to this job [default: none]
> On Dec 22, 2014, at 1:29 PM, Saliya Ekanayake <[email protected]> wrote:
>
> Thank you and one last question. Is it possible to avoid a core and instruct
> OMPI to use only the other cores?
>
> On Mon, Dec 22, 2014 at 2:08 PM, Ralph Castain <[email protected]
> <mailto:[email protected]>> wrote:
>
>> On Dec 22, 2014, at 10:45 AM, Saliya Ekanayake <[email protected]
>> <mailto:[email protected]>> wrote:
>>
>> Hi Ralph,
>>
>> Yes the report bindings show the correct binding as expected for the
>> processes. The doubt I am having is, say I spawn a thread within my process.
>> If I don't specify affinity for it, is it possible for it to get scheduled
>> to run in a core outside that of the process?
>
> It shouldn’t, unless you deliberately unbind it.
>
>>
>> Second question is, does MPI provides an API such that I can retrieve the
>> binding info from program to take decisions on setting thread affinity?
>
> Nothing specifically in the standard, no. There has been some discussion on
> this list about ways of getting the info, though they all involve a
> collective operation. I’m working on an MPI extension for OMPI to access it
> as each proc already has binding/location info for every proc in the job -
> just no MPI standard way of providing it to you.
>
>
>>
>> Thank you,
>> Saliya
>>
>> On Mon, Dec 22, 2014 at 1:18 PM, Ralph Castain <[email protected]
>> <mailto:[email protected]>> wrote:
>> FWIW: it looks like we are indeed binding to core if PE is set, so if you
>> are seeing something different, then we may have a bug somewhere.
>>
>> If you add —report-bindings to your cmd line, you should see where we bound
>> the procs - does that look correct?
>>
>>
>>> On Dec 22, 2014, at 9:49 AM, Ralph Castain <[email protected]
>>> <mailto:[email protected]>> wrote:
>>>
>>> They will be bound to whatever level you specified - I believe by default
>>> we bind to socket when mapping by socket. If you want them bound to core,
>>> you might need to add —bind-to core.
>>>
>>> I can take a look at it - I *thought* we had reset that to bind-to core
>>> when PE=N was specified, but maybe that got lost.
>>>
>>>
>>>> On Dec 22, 2014, at 8:32 AM, Saliya Ekanayake <[email protected]
>>>> <mailto:[email protected]>> wrote:
>>>>
>>>> Hi,
>>>>
>>>> I've been using --map-by socket:PE=N, where N is used to control the
>>>> number of cores a proc gets mapped to. Does this also guarantee that a
>>>> proc is bound to N cores in the socket? I am asking this because I see
>>>> some threads spawned by the process run outside the given N cores in the
>>>> socket.
>>>>
>>>> Is this expected or I guess I am missing some binding parameter here?
>>>> Also, is there some documentation on these different choices? Are the
>>>> options in [1] available in current release?
>>>>
>>>> [1]
>>>> http://www.slideshare.net/jsquyres/open-mpi-explorations-in-process-affinity-eurompi13-presentation
>>>>
>>>> <http://www.slideshare.net/jsquyres/open-mpi-explorations-in-process-affinity-eurompi13-presentation>
>>>>
>>>> Thank you,
>>>> Saliya
>>>>
>>>> --
>>>> Saliya Ekanayake
>>>> Ph.D. Candidate | Research Assistant
>>>> School of Informatics and Computing | Digital Science Center
>>>> Indiana University, Bloomington
>>>> Cell 812-391-4914 <tel:812-391-4914>
>>>> http://saliya.org
>>>> <http://saliya.org/>_______________________________________________
>>>> users mailing list
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>>>> Link to this post:
>>>> http://www.open-mpi.org/community/lists/users/2014/12/26051.php
>>>> <http://www.open-mpi.org/community/lists/users/2014/12/26051.php>
>>
>>
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>> http://www.open-mpi.org/community/lists/users/2014/12/26054.php
>> <http://www.open-mpi.org/community/lists/users/2014/12/26054.php>
>>
>>
>>
>> --
>> Saliya Ekanayake
>> Ph.D. Candidate | Research Assistant
>> School of Informatics and Computing | Digital Science Center
>> Indiana University, Bloomington
>> Cell 812-391-4914 <tel:812-391-4914>
>> http://saliya.org
>> <http://saliya.org/>_______________________________________________
>> users mailing list
>> [email protected] <mailto:[email protected]>
>> Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users
>> <http://www.open-mpi.org/mailman/listinfo.cgi/users>
>> Link to this post:
>> http://www.open-mpi.org/community/lists/users/2014/12/26056.php
>> <http://www.open-mpi.org/community/lists/users/2014/12/26056.php>
>
> _______________________________________________
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> Link to this post:
> http://www.open-mpi.org/community/lists/users/2014/12/26057.php
> <http://www.open-mpi.org/community/lists/users/2014/12/26057.php>
>
>
>
> --
> Saliya Ekanayake
> Ph.D. Candidate | Research Assistant
> School of Informatics and Computing | Digital Science Center
> Indiana University, Bloomington
> Cell 812-391-4914
> http://saliya.org
> <http://saliya.org/>_______________________________________________
> users mailing list
> [email protected]
> Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users
> Link to this post:
> http://www.open-mpi.org/community/lists/users/2014/12/26058.php
