2011/11/18 George Bosilca <firstname.lastname@example.org>
On Nov 18, 2011, at 07:29 , Hugo Daniel Meyer wrote:
I was doing some trace into de PML_OB1 files. I start to follow a MPI_Ssend() trying to find where a message is stored (in the sender) if it is not send until the receiver post the recv, but i didn't find that place.
Right, you can't find this as the message is not stored on the sender. The pointer to the send request is sent encapsulated in the matching header, and the receiver will provide it back once the message has been matched (this means the data is now ready to flow).
So, what you're saying is that the sender only sends the header, so when the receiver post the recv will send again the header so the sender starts with the data sent? am i getting it right? If this is ok, the data stays in the sender, but where it is stored?