[mpich-discuss] running out of communicators

[Jim Dinan]

Hi Ryan,

MPI_File_open does call MPI_Comm_dup internally.  How many files are you 
opening?  And are you closing them when you're finished with them?

  ~Jim.

On 3/19/13 8:20 PM, Ryan Crocker wrote:
> Hi Jim,
>
> That's the thing, i'm not sure where they are being created.  I initialize my MPI environment, then that program never gets called again.  The only think i can think of is that it's something to do with my MPI IO, but after every open file, i just double checked, there is a corresponding close file call. I also do not call MPI_Comm_dup, unless that is called by another mpi call that i am not aware of.
>
> -Ryan
>
> On Mar 19, 2013, at 6:13 PM, Jim Dinan wrote:
>
>> Hi Ryan,
>>
>> Every time you call MPI_Comm_dup a new communicator is created.  Are you ever freeing these, using MPI_Comm_free?
>>
>> Also, what are you trying to achieve by using multiple communicators, and why does it require so many?
>>
>> Best,
>> ~Jim.
>>
>> On 3/19/13 7:57 PM, Ryan Crocker wrote:
>>> I realized i forgot to attach the error:
>>>
>>> Fatal error in PMPI_Comm_dup: Other MPI error, error stack:
>>> PMPI_Comm_dup(176)............: MPI_Comm_dup(comm=0x84000000, new_comm=0x7fff5fbfe9a4) failed
>>> PMPI_Comm_dup(161)............:
>>> MPIR_Comm_dup_impl(55)........:
>>> MPIR_Comm_copy(967)...........:
>>> MPIR_Get_contextid(521).......:
>>> MPIR_Get_contextid_sparse(752): Too many communicators
>>>
>>> Hi all,
>>>
>>> So i can't seem to find the answer to this question.  I keep getting the failure "Too many communicators".  Could someone explain what calls "use up" communicators, and could i be calling/using more than the default total?.  I'm trying to debug my code so i can free up the communicators and not just repeatedly create them.  I'm a bit perplexed with this, probably a lack of  in depth knowledge, but i only run any of my MPI initializations one time then all my calls with mpi are either sums, max, min, allreduce, alltoall.
>>>
>>> thanks
>>>
>>> Ryan Crocker
>>> University of Vermont, School of Engineering
>>> Mechanical Engineering Department
>>> rcrocker at uvm.edu
>>> 315-212-7331
>>>
>>> _______________________________________________
>>> discuss mailing list     discuss at mpich.org
>>> To manage subscription options or unsubscribe:
>>> https://lists.mpich.org/mailman/listinfo/discuss
>>>
>> _______________________________________________
>> discuss mailing list     discuss at mpich.org
>> To manage subscription options or unsubscribe:
>> https://lists.mpich.org/mailman/listinfo/discuss
>
> Ryan Crocker
> University of Vermont, School of Engineering
> Mechanical Engineering Department
> rcrocker at uvm.edu
> 315-212-7331
>
> _______________________________________________
> discuss mailing list     discuss at mpich.org
> To manage subscription options or unsubscribe:
> https://lists.mpich.org/mailman/listinfo/discuss
>