At 10:00 PM 10/23/2006, Greg Lindahl wrote: >On Mon, Oct 23, 2006 at 07:53:06AM -0500, Hubbell, Sean C >Contractor/Decibel wrote: > > > I currently have several applications that uses a legacy IPv4 protocol > > and I use IPoIB to utilize my infiniband network which works great. I > > have completed some timing and throughput analysis and noticed that I do > > not get very much more if I use an infiniband network interface than > > using my GigE network interface. > >You might want to note that different InfinBand implementations have >quite different performance of IPoIB, especially for UDP. > >Another issue is that IPoIB has quite different performance with >different Linux kernels. This is especially evident for TCP, although >you can use SDP to accelerate TCP sockets and avoid this issue. > > > My question is, am I using IPoIB correctly or are these the typical > > numbers that everyone is seeing? > >It is certainly the case that there are some message patterns and >situations for which InfiniBand is not much of an improvement over >gigE.
Unfortunately, the comparison of IB to GbE are often apple-to-orange comparisons even for IP over IB. Until a HCA supplies the same level of functional off-load enabled by the IP network stack that is used with Ethernet, it really isn't a fair comparison. The same is also true for many of the marketroids and their comparisons of IB to Ethernet based solutions. Fortunately, most customers are getting a bit smarter and not falling for the marketing drivel these days - certainly the OEM don't fall for it thought the marketroids continue to come in and try to convince people it isn't an apple-to-orange comparison. The fact is both technologies have their pros / cons and it is really the workload or production environment that determines which is the best fit instead of the force fit. In any case, not really a development issue so will drop further discussion. Mike _______________________________________________ openib-general mailing list [email protected] http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
