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From: Galen Shipman (gshipman_at_[hidden])
Date: 2007-05-27 12:26:33


doh,, correction..

On May 27, 2007, at 10:23 AM, Galen Shipman wrote:

>>>
>>>
>>> The problem is that MCA_BTL_DES_FLAGS_PRIORITY was meant to
>>> indicate
>>> that the fragment was higher priority, but the fragment isn't higher
>>> priority. It simply needs to be ordered w.r.t. a previous fragment,
>>> an RDMA in this case.
>> But after the change priority flags is totally ignored.
>>
>
>
> So the priority flag was broken I think, in OpenIB we used the
> priority flag to choose a QP on which to send the fragment, but there
> was no checking for if the fragment could be sent on the specified
> QP. So a max send size fragment could be set as priority and the BTL
> would use the high priority QP and we would go bang. This is how I
> read the code, I might have missed something.
>
> If the priority flag is simply a "hint" and has
*NO*
> hard requirements
> than we can still use it in the OpenIB BTL but it won't have any
> effect as only eager size fragments can be marked high priority and
> we already send these over the high priority QP.
>
> - Galen
>
>
>
>
>>
>> --
>> Gleb.
>> <patch.diff>
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