> > - isn't Mellanox still the sole source for IB chips, for both > > nics and switches? this seems odd if it's a thriving ecosystem. > > no offense intended! yes, I know quadrics/SGI/SCI/Myri are all > > also sole-source. but compared to the eth world... > > Mellanox is not the sole source for InfiniBand chips. There are other > vendors like Qlogic and IBM that have InfiniBand chips. As InfiniBand
hmm, I know various people have produced IB chips, but I haven't seen any in actual use. oh, wait, qlogic - you mean pathscale infinipath. yes, certainly, though it's worth noting that the interesting part of their product specifically just hijacks IB for their own faster MPI protocol ;) not unlike octigabay/cray-xd1, come to think of it, and not really _that_ far from the Horus folk using IB phy layers for their non-IB fabric. > > - price of nics has gone down significantly, close to the point > > of no resistance. but afaikt, IB switching is still a big cost; > > are there prospects of IB switch fabrics getting anywhere close > > to gigabit costs? > > Its all customers demand. The market pushes the price down and we see > the results already. Mellanox ASIC is $69 and adapter is $125 OEM price. what puzzles me is that market-push-down has apparenly only driven the prices of nics down. that's a bit silly, since surely shaving $10 of memory off a $100 nic hurts performance, especially when the majority of the installation's cost is in switch+cable (at least 5x the nic cost, no?) > > - IB people seem to be claiming quite nice latency figures > > these days, but I don't really understand what changed to cause > > a ~7x reduction in latency. > > In one word experience. In the early days, IB was not design for high > performance but for other reasons. But if you can get high BW and low > latency then why not... Mellanox increases the performance from > generation to generation, and the latency we see today from multiple > vendors are quite nice figures.. I'm afraid that upon reading this response and thinking about it, I know no more than before ;( > 10GigE people need to solve problems that do not exist in IB, and the > 10GigE solutions for those issues will results in more expensive NICs. but it's silly to only focus on nic prices. I fully expect a myrinet 10gbase-t nic to cost at least around $500. that sounds like a lot more than a memfree IB nic, but if IB switch ports cost more than 10gbase-t ports, it may be irrelevant. besides, I'd actually prefer to pay a bit more for my nics - to put intelligence in the nic rather than the switch. _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
