parallel processing - understanding MPI send differences -

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ok let's start, i've bit of confusion in head.

send: blocking. sender waits until receiver has posted corresponding recv.

ssend: blocking , sender not waits until receiver has posted corresponding recv, wait ack of recv. means recv run fine.

bsend: non blocking. process can go ahead execute part of code. data stored in buffer allocated before.

isend: non blocking. process can go ahead execute part of code. data not stored in buffer: must not overwrite data you're sending until you're sure isend has run fine (wait/ test).

so.. isend , bsend differs buffer?

yes--the difference between isend , bsend buffer.

isend non-blocking send performed in-place.

bsend non-blocking send can buffered in segment of memory specified mpi_buffer_attach.

the bsend function created allow programmer specify data being buffered.

it important note that, isend, must check status of sends using bsend buffer not overflow buffer or overwrite pending bsend's.


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