Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

Subject: Re: [OMPI users] btl_openib_cpc_include rdmacm questions
From: Brock Palen (brockp_at_[hidden])
Date: 2011-05-17 14:18:35


Sorry typo 314 not 313,

Brock Palen
www.umich.edu/~brockp
Center for Advanced Computing
brockp_at_[hidden]
(734)936-1985

On May 17, 2011, at 2:02 PM, Brock Palen wrote:

> Thanks, I though of looking at ompi_info after I sent that note sigh.
>
> SEND_INPLACE appears to help performance of larger messages in my synthetic benchmarks over regular SEND. Also it appears that SEND_INPLACE still allows our code to run.
>
> We working on getting devs access to our system and code.
>
> Brock Palen
> www.umich.edu/~brockp
> Center for Advanced Computing
> brockp_at_[hidden]
> (734)936-1985
>
>
>
> On May 16, 2011, at 11:49 AM, George Bosilca wrote:
>
>> Here is the output of the "ompi_info --param btl openib":
>>
>> MCA btl: parameter "btl_openib_flags" (current value: <306>, data
>> source: default value)
>> BTL bit flags (general flags: SEND=1, PUT=2, GET=4,
>> SEND_INPLACE=8, RDMA_MATCHED=64, HETEROGENEOUS_RDMA=256; flags
>> only used by the "dr" PML (ignored by others): ACK=16,
>> CHECKSUM=32, RDMA_COMPLETION=128; flags only used by the "bfo"
>> PML (ignored by others): FAILOVER_SUPPORT=512)
>>
>> So the 305 flags means: HETEROGENEOUS_RDMA | CHECKSUM | ACK | SEND. Most of these flags are totally useless in the current version of Open MPI (DR is not supported), so the only value that really matter is SEND | HETEROGENEOUS_RDMA.
>>
>> If you want to enable the send protocol try first with SEND | SEND_INPLACE (9), if not downgrade to SEND (1)
>>
>> george.
>>
>> On May 16, 2011, at 11:33 , Samuel K. Gutierrez wrote:
>>
>>>
>>> On May 16, 2011, at 8:53 AM, Brock Palen wrote:
>>>
>>>>
>>>>
>>>>
>>>> On May 16, 2011, at 10:23 AM, Samuel K. Gutierrez wrote:
>>>>
>>>>> Hi,
>>>>>
>>>>> Just out of curiosity - what happens when you add the following MCA option to your openib runs?
>>>>>
>>>>> -mca btl_openib_flags 305
>>>>
>>>> You Sir found the magic combination.
>>>
>>> :-) - cool.
>>>
>>> Developers - does this smell like a registered memory availability hang?
>>>
>>>> I verified this lets IMB and CRASH progress pass their lockup points,
>>>> I will have a user test this,
>>>
>>> Please let us know what you find.
>>>
>>>> Is this an ok option to put in our environment? What does 305 mean?
>>>
>>> There may be a performance hit associated with this configuration, but if it lets your users run, then I don't see a problem with adding it to your environment.
>>>
>>> If I'm reading things correctly, 305 turns off RDMA PUT/GET and turns on SEND.
>>>
>>> OpenFabrics gurus - please correct me if I'm wrong :-).
>>>
>>> Samuel Gutierrez
>>> Los Alamos National Laboratory
>>>
>>>
>>>>
>>>>
>>>> Brock Palen
>>>> www.umich.edu/~brockp
>>>> Center for Advanced Computing
>>>> brockp_at_[hidden]
>>>> (734)936-1985
>>>>
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Samuel Gutierrez
>>>>> Los Alamos National Laboratory
>>>>>
>>>>> On May 13, 2011, at 2:38 PM, Brock Palen wrote:
>>>>>
>>>>>> On May 13, 2011, at 4:09 PM, Dave Love wrote:
>>>>>>
>>>>>>> Jeff Squyres <jsquyres_at_[hidden]> writes:
>>>>>>>
>>>>>>>> On May 11, 2011, at 3:21 PM, Dave Love wrote:
>>>>>>>>
>>>>>>>>> We can reproduce it with IMB. We could provide access, but we'd have to
>>>>>>>>> negotiate with the owners of the relevant nodes to give you interactive
>>>>>>>>> access to them. Maybe Brock's would be more accessible? (If you
>>>>>>>>> contact me, I may not be able to respond for a few days.)
>>>>>>>>
>>>>>>>> Brock has replied off-list that he, too, is able to reliably reproduce the issue with IMB, and is working to get access for us. Many thanks for your offer; let's see where Brock's access takes us.
>>>>>>>
>>>>>>> Good. Let me know if we could be useful
>>>>>>>
>>>>>>>>>> -- we have not closed this issue,
>>>>>>>>>
>>>>>>>>> Which issue? I couldn't find a relevant-looking one.
>>>>>>>>
>>>>>>>> https://svn.open-mpi.org/trac/ompi/ticket/2714
>>>>>>>
>>>>>>> Thanks. In csse it's useful info, it hangs for me with 1.5.3 & np=32 on
>>>>>>> connectx with more than one collective I can't recall.
>>>>>>
>>>>>> Extra data point, that ticket said it ran with mpi_preconnect_mpi 1, well that doesn't help here, both my production code (crash) and IMB still hang.
>>>>>>
>>>>>>
>>>>>> Brock Palen
>>>>>> www.umich.edu/~brockp
>>>>>> Center for Advanced Computing
>>>>>> brockp_at_[hidden]
>>>>>> (734)936-1985
>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Excuse the typping -- I have a broken wrist
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> users mailing list
>>>>>>> users_at_[hidden]
>>>>>>> http://www.open-mpi.org/mailman/listinfo.cgi/users
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> users mailing list
>>>>>> users_at_[hidden]
>>>>>> http://www.open-mpi.org/mailman/listinfo.cgi/users
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> users mailing list
>>>>> users_at_[hidden]
>>>>> http://www.open-mpi.org/mailman/listinfo.cgi/users
>>>>>
>>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> users mailing list
>>>> users_at_[hidden]
>>>> http://www.open-mpi.org/mailman/listinfo.cgi/users
>>>
>>>
>>> _______________________________________________
>>> users mailing list
>>> users_at_[hidden]
>>> http://www.open-mpi.org/mailman/listinfo.cgi/users
>>
>> George Bosilca
>> Research Assistant Professor
>> Innovative Computing Laboratory
>> Department of Electrical Engineering and Computer Science
>> University of Tennessee, Knoxville
>> http://web.eecs.utk.edu/~bosilca/
>>
>>
>> _______________________________________________
>> users mailing list
>> users_at_[hidden]
>> http://www.open-mpi.org/mailman/listinfo.cgi/users
>>
>>
>
>
> _______________________________________________
> users mailing list
> users_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/users
>
>