On Thu, 2008-05-29 at 15:35 +0200, Marcel Heinz wrote: > Hal Rosenstock wrote: > > On Thu, 2008-05-29 at 11:19 +0200, Marcel Heinz wrote: > >>Dotan Barak wrote: > >>>Marcel Heinz wrote: > >>> > >>>>[low multicast throughput of ~250MB/s with own benchmark tool] > >>> > >>>1) I know that ib_send_bw supports multicast as well, can you please > >>>check that you can reproduce your problem > >>>on this benchmark too? > >> > >>| #bytes #iterations BW peak[MB/sec] BW average[MB/sec] > >>| 2048 1000 301.12 247.05 > >> > >>This is the same result as my own benchmark showed in that scenario. > >> > >> > >>>2) You should expect that multicast messages will be slower than > >>>unicast because the HCA/switch treat them in different way > >>>(message duplication need to be done if needed). > >> > >>Yes, but 250MB/s vs. 1100MB/s (UD unicast throughput) seems to be a bit > >>too much of overhead, don't you think? > > > > > > Agreed. > > > > > >>Especially if I take into account > >>that with my own benchmark, I can get ~950MB/s when I start another > >>receiver on the same host as the sender. Note that both of the > >>receivers, the local and the remote one, are seeing all packets at that > >>rate, so the HCAs and the switch must be able to handle multicast > >>packets with this throughput. > > > > > > Perhaps this is a static rate issue. > > > > What SM is being used ? > > It's OpenSM 3.1.7. I had also made some tests with OpensSM 3.2.1, but > this didn't change anything.
Can you validate either the PathRecord or MCMemberRecord returned or the static rate applied to the multicast QP in the various scenarios ? If it is the same, this is not the problem but if it's different then we're on to something here. -- Hal > Regards, > Marcel > > > _______________________________________________ > general mailing list > [email protected] > http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general > > To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general _______________________________________________ general mailing list [email protected] http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
