On Tue, 29 Jul 2008, Steve Wise wrote:
> Caitlin Bestler wrote: > > On Tue, Jul 29, 2008 at 9:47 AM, Felix Marti <[EMAIL PROTECTED]> wrote: > > > > > > > Roland, AFAIK, even an unsignaled WR generates a CQE when an error > > > occurs (and then all subsequent WRs complete in error as well). Doesn't > > > that imply that the CQ must be sized assuming that _every_ WR can > > > generate a CQE? > > > > > > > > > > Yes, that is exactly what application writers should assume. > > > > They should also assume that spurious completion interrupts are possible > > (although obviously they should be minimized) and therefore the application > > should always be ready be woken up early and find nothing to do. > > > > More complete descriptions that could be used as guidelines can be found > > in the DAPL manuals. > > > > About the only thing I think that can be done about this specific quirk is > > to document it so that application developers are aware of it, and know that > > it is a model-specific limitation and do not think it is a limitation of > > RDMA > > or iWARP. If their application does not need the notification it should > > keep requesting unsignaled completion. > > > Well if applications should handle infrequent spurious notifcations > where no cqe is available, then I can indeed add code in my provider > poll to silently throw away unsignaled read completions. Did you consider returning an error from ib_post_send to indicate that an unsignalled RDMA read is not supported? james _______________________________________________ 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
