GitLab

by inspection in Pstreams/exchange.C

The number of exchange iterations is calculated with the byte count:

nIter = (maxNBytes-1)/Pstream::maxCommsSize+1;

but later on in the loop the send sizes per iteration are calculated in the element count, not the byte count:

nSend[proci] = min
(
    Pstream::maxCommsSize,
    sendBufs[proci].size()-startSend[proci]
);

// and
charSendBufs[proci] = reinterpret_cast<const char*>
(
    &(sendBufs[proci][startSend[proci]])
);

I think that requested Pstream::maxCommsSize needs to be translated into a maxNumElems, with the appropriate sizeof(T) granularity and that is what should be used.

@Mattijs for comments?