[mvapich-discuss] MVAPICH1 Latency Tuning

[Sayantan Sur]

Hi Hideyuki,

On Thu, Mar 11, 2010 at 10:25 AM, Hideyuki Jitsumoto
<jitumoto at gsic.titech.ac.jp> wrote:
> Sayantan,
>
> Thank you for your reply.
> I'm sorry about unclear information about the application,
> because this application is our supercomputer user's.
>
> Then I need to ask the user the detail of this application.
> Probably I'll send you a correct information on Monday.
>

Looking forward to hearing from you after you get more information
from the user.

> I'm in flight 10 hours from now, then I'm sorry that I cannot send any
> information.
>
> # I wonder I saw you on a taxi toward MPI Forum ?

Yes! I thought the name sounded familiar :-) It was good meeting you
at the forum. Hope to meet you at future forums or on the sidelines of
ICS in Japan later this year.

Thanks.

>
> Thank you,
> Hideyuki
>
> On Wed, Mar 10, 2010 at 8:18 PM, Sayantan Sur <surs at cse.ohio-state.edu> wrote:
>> Hi Hideyuki,
>>
>> On Wed, Mar 10, 2010 at 2:34 PM, Hideyuki Jitsumoto
>> <jitumoto at gsic.titech.ac.jp> wrote:
>>> Hello,
>>>
>>> I want to reduce the latency and memory use with MVAPICH1.
>>> My MPI application has:
>>> - < 128KB message size
>>> - 4 peer connection for one process
>>>
>>> I make the temporary paramfile as attached file.
>>> Please tell me other tuning point or wrong parameter on this file.
>>
>> Thanks for your question. It is an important question. We would be
>> happy to assist you with tuning MVAPICH for your application.
>>
>> I took a quick look at the param file. Based on what I see, I think
>> some parameters relating to rendezvous protocol are not optimal at
>> all. We need to understand your application a little bit more to be
>> able to help you better. So, a few questions:
>>
>> 1) Do you know how many concurrent outstanding sends your application
>> has during its iteration steps?
>> 2) Can you share a code snippet of the inner loop of your application?
>> 3) Which InfiniBand adapters do you have on your cluster?
>> 4) What is the node type, number of cores?
>>
>> This will help us to send you a better send of parameters in the next few days.
>>
>>>
>>> Thank you,
>>> Hideyuki
>>> --
>>> Sincerely Yours,
>>> Hideyuki Jitsumoto (jitumoto at gsic.titech.ac.jp)
>>> Tokyo Institute of Technology
>>> Global Scientific Information and Computing center (Matsuoka Lab.)
>>>
>>> _______________________________________________
>>> mvapich-discuss mailing list
>>> mvapich-discuss at cse.ohio-state.edu
>>> http://mail.cse.ohio-state.edu/mailman/listinfo/mvapich-discuss
>>>
>>>
>>
>>
>>
>> --
>> Sayantan Sur
>>
>> Research Scientist
>> Department of Computer Science
>> The Ohio State University.
>>
>
>
>
> --
> Sincerely Yours,
> Hideyuki Jitsumoto (jitumoto at gsic.titech.ac.jp)
> Tokyo Institute of Technology
> Global Scientific Information and Computing center (Matsuoka Lab.)
>
>



-- 
Sayantan Sur

Research Scientist
Department of Computer Science
The Ohio State University.