> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Guy German > Sent: Wednesday, September 21, 2005 12:59 AM > To: Sean Hefty > Cc: Openib > Subject: Re: [openib-general][PATCH][RFC]: CMA IB implementation > > Sean Hefty wrote: > > Guy German wrote: > >> static void cma_route_handler(u64 req_id, void *context, > int rec_num) > >> { > >> status = ib_at_paths_by_route(&cma_ctx->cma_route, 0, > >> &cma_ctx->cma_path, 1, > >> &cma_ctx->ibat_comp); } int > >> ib_cma_connect(struct ib_cma_conn *cma_conn, void **cma_id) { > >> status = ib_at_route_by_ip(dst_ip, 0, 0, 0, > &cma_ctx->cma_route, > >> &cma_ctx->ibat_comp); }; > > > > I still think that it may be better for the user to get the > route/path > > separately from establishing a connection. This simplifies the > > internal state handling, and I believe maps better to the user > > allocating the QP, transitioning it to the INIT state, and > pre-posting > > receive buffers. An application may want to change its > behavior based > > on its path (such as MTU or data rate). Integrating this in > with the > > connect call requires applications that want to do this to operate > > with the lower level connection interfaces. > > The problems I see with asynchronous route/arp model in the > generic cm API is that consumers will have to deal with > complicated caching (that can be implemented in the at > module) and that it is not native to iwarp. > > What do other people think about it ? >
Any split in the API needs to allow iWARP providers to implement the first part as a nop. iWARP is defined on top of IP transports, and in fact frequently is cleanly layered over at least the IP layer (full clean separation from the TCP layer being a bit less common). So the iWARP implementation may literally have no access to ARP data. Ultimately, that is an extreme example of the caching benefits Guy referenced even for IB providers. My question on this remains, what applications would really use this split? And wouldn't the speciail requirements of these applications, which I believe is a subset even of appliations that know they are using InfiniBand, mean that they would use the IB specific CM API (with explicit CM MADs)? _______________________________________________ openib-general mailing list [email protected] http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
