In early August virtualization.info broke the news about Infiniband support in the upcoming ESX Server 3.5.
Now that the product is about to ship, Mellanox officially announces its involvement:
Mellanox Technologies, Ltd., a leading supplier of semiconductor-based, server and storage interconnect products, today announced that later this year VMware is expected to provide enablement for Mellanox InfiniBand-based adapters in the newest release of VMware Infrastructure, which includes VMware ESX Server 3.5 and VMware VirtualCenter 2.5. The InfiniBand LAN networking and block storage drivers are based on the OpenFabrics Enterprise Distribution (OFED) version 1.2.5 and were developed by Mellanox, VMware and other participants of the VMware Community Source program.
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When InfiniBand I/O adapters are used with VMware ESX Server 3.5, a single adapter can replace multiple gigabit Ethernet NICs and Fibre Channel HBAs while maintaining or enhancing I/O throughput from virtual machines. For example, SAN throughput from a virtual machine can reach up to 1500 Megabytes per second (MB/s) or it can be shared linearly across multiple virtual machines, e.g., about 400 MB/s per virtual machine across four virtual machines on the same VMware ESX Server host. This is equivalent to using four 4 Gb/s Fibre Channel HBAs, one dedicated to each of the four virtual machines. This I/O consolidation and scale out, which results in significant cost and power savings, is achieved transparently as operating systems and applications running in the virtual machines continue to run over traditional virtual NIC and HBA interfaces available in VMware virtual machines. Network and storage I/O provisioning for virtual machines and features like VMware VMotion are also configured transparently using VMware VirtualCenter 2.5, which exposes only the familiar virtual NIC and virtual HBA interfaces available over the unified InfiniBand I/O adapter. Similarly, features such as high availability and migration of virtual machines are preserved as if they were operating on Ethernet NICs and Fibre Channel HBAs…
Massimo Re Ferrè, IT Architect at IBM, published on his personal blog an article comparing InfiniBand with 10Gbit Ethernet which is a worth reading.