On Fri, 2007-04-13 at 02:17, Michael S. Tsirkin wrote: > > Quoting Sean Hefty <[EMAIL PROTECTED]>: > > Subject: RE: [ofa-general] Re: multicast join failed for... > > > > >When the node is diagnosed and disconnected, SM will bring the rate > > >back up. > > > > But how? Doesn't it require re-registration of all multicast groups and > > clients registered for SA events? > > SA detects that rate can be increased and sends another reregister MAD.
Nit: it would be the SM rather than SA which would detect this and reregister (which is an SM PortInfo change). That causes the SA clients to do a lot of SA things. > > >As I said, there are tens of ways a bad node can hurt performance, > > >and we don't/can't handle them. Why focus on ipoib? It's > > >the only way to connect to node on some fabrics, it > > >really must be up at all times. > > > > But the solution is affecting all multicast traffic, not just that > > related to ipoib. If you want all nodes to be able to join the ipoib > > multicast group, why not just create the group at the lower rate? > > If the group is created at a lower rate, there would be no problem. > But the default configuration should be "plug an play". So you are arguing for 1x SDR as the default. We've discussed and disagreed on this before as I think it masks performance issues and those are harder to find. I could be wrong about this. > > ipoib multicast performance doesn't seem that critical. > > This is a policy than can be made optional, but should not > be forced on users by default. > > > Whereas disrupting > > other multicast groups, which could actively be in use by MPI, may be. > > The disruption would be very minor - this would happen at most once when rate > changes > from DDR to SDR and once when it changes back. In frequency it may be minor. It affects other things that should not be affected. Perhaps that is just a shortcoming of the mechanism underneath and that can/should be improved. -- Hal _______________________________________________ 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
