> From: David Nolan [mailto:[email protected]] > > cut-through switching where the packet has started leaving the switch > before it's even fully arrived.
The OP said they were looking at FCoE as a cheaper alternative to FC due to management budget constraint. Entry level Infiniband is about $3k-$4k for the switch and about $400 for each of the HCA's. This is 40Gbit with 200ns latency, RDMA bypassing the OSI stack, and credit-based flow control, which is better than ethernet flow control. This is the lowest cost IB solution, and from this starting point, you can very easily expand and grow capacity and speed if you need to. Entry level 10Ge is about $1k-$2k for the switch (such as Netgear XS712T and similar series) and about $330 for each NIC. This is 10Gbit, store-and-forward, and lacks all of the above described performance features, but hey, it's cheaper. By the time you upgrade your 10Ge to include HBA's with iscsi offload, and cut-through switching, you're going to pay as much as the IB network, but you will be absolutely maxed out (there is nothing higher than 10Gbit ether) and you're nowhere near performance-competitive versus the comparably priced IB solution. You've got 10Gbit with "as low as 1us" latency, and inferior flow control. The only reason to go 10Ge is price constraint, which keeps you down in the store-and-forward and software iscsi class of solution. I have not explicitly looked into FC for comparison. _______________________________________________ Discuss mailing list [email protected] https://lists.lopsa.org/cgi-bin/mailman/listinfo/discuss This list provided by the League of Professional System Administrators http://lopsa.org/
