Mellanox announced this week that they’re introducing
…the industry’s highest performing 20Gb/s InfiniBand and 10 Gigabit Ethernet adapters accelerated by PCI Express 2.0 with 5GT/s support (PCIe Gen2), doubling the bandwidth to host processors.
Lots of PR-speak in the press release, which also includes performance numbers. Here are the MPI numbers quoted
PCIe Gen2 enables 1850MB/s uni-directional and 3650MB/s bi-directional MPI throughput over a single 20Gb/s InfiniBand port which is approximately a 30% increase over platforms that only support PCI Express 1.1 (PCIe Gen1). Two active 20Gb/s InfiniBand ports saturate the total PCIe Gen2 x8 interface with over 5500MB/s of bi-directional bandwidth (a 100% increase over PCIe Gen1 platforms). Latency for MPI message transfers is reduced up to 25%.