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From: Doug Gregor (dgregor_at_[hidden])
Date: 2008-05-27 14:52:44


On May 22, 2008, at 4:40 PM, Doug Gregor wrote:

> 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.

Done; it's called Count.

>> 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.

Fixed.

>> 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.

There was an issue where the CompletedStatus object returned from
Wait() and Test() did not have the Cancelled property set after the
request had been cancelled. If you are seeing any other issues here,
please tell me!

   - Doug