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From: Doug Gregor (dgregor_at_[hidden])
Date: 2008-05-22 16:40:49


Hi Robert,

On May 19, 2008, at 6:05 PM, Robert Palmer wrote:
> I am a program manager at MS in the HPC group. I have been playing
> with the MPI .net distribution for a bit now and have a couple of
> questions. Thanks in advance for the tips!
>
> 1. Is there some way to determine the length of a RequestList?

No, but there should be. I'll add a Length property.

> 2. Sometimes Test() returns a non-null value on a receive
> request and the corresponding CompletedStatus.Source field is set to
> -2 (negative two).

This has been on my TODO list for a while; it's a bug, I'll fix it.

> 3. I am expecting the obj.Test() to return a handle to the
> same CompletedStatus every time I call it – is this an incorrect
> assumption?

No, that should be what is happening; we cache the CompletedStatus
internally. You're getting different CompletedStatus objects?

> 4. Is Cancel() working on requests?

It should be, but remember that MPI's cancel can have some strange
semantics. For example, canceling a send may or may not actually
cancel the communication, depending on where in the communication the
underlying MPI library (and the hardware) actually are. Cancel is
better applied to receive requests than send requests.

   - Doug