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Subject: Re: [OMPI devel] RFC: sm Latency
From: Richard Graham (rlgraham_at_[hidden])
Date: 2009-01-22 10:29:45


BTW,
    In the recvi function, do you first try to match off the unexpected list
before you try and match data in the fifo¹s ?

Rich

On 1/21/09 8:00 PM, "Eugene Loh" <Eugene.Loh_at_[hidden]> wrote:

> Ron Brightwell wrote:
>>
>>>
>>> If you poll only the queue that correspond to a posted receive, you only
>>> optimize micro-benchmarks, until they start using ANY_SOURCE.
>>>
>>>
>>
>> Note that the HPCC RandomAccess benchmark only uses MPI_ANY_SOURCE (and
>> MPI_ANY_TAG).
>>
> But HPCC RandomAccess also just uses non-blocking receives. So, it's kind of
> outside the scope of the original ideas here (bypassing the PML
> receive-request data structure).
>
> It's possibly not even a poster child for the single-queue idea either.
> Single queue probably shines best when you have to poll all connections for a
> few messages. In contrast, RandomAccess (I think) loads all connections up
> randomly (pseudo-evenly).
>