On Wed, 12 Dec 2007, Gleb Natapov wrote:
On Wed, Dec 12, 2007 at 03:46:10PM -0500, Richard Graham wrote:
This is better than nothing, but really not very helpful for looking at the
specific issues that can arise with this, unless these systems have several
parallel networks, with tests that will generate a lot of parallel network
traffic, and be able to self check for out-of-order received - i.e. this
needs to be encoded into the payload for verification purposes. There are
some out-of-order scenarios that need to be generated and checked. I think
that George may have a system that will be good for this sort of testing.
I am running various test with multiple networks right now. I use
several IB BTLs and TCP BTL simultaneously. I see many reordered
messages and all tests were OK till now, but they don't encode
message sequence in a payload as far as I know. I'll change one of
them to do so.
Other than Rich's comment that we need sequence numbers, why add them? We
haven't had them for non-matching packets for the last 3 years in Open MPI
(ie, forever), and I can't see why we would need them. Yes, we need
sequence numbers for match headers to make sure MPI ordering is correct.
But for the rest of the payload, there's no need with OMPI's datatype
engine. It's just more payload for no gain.
Brian
