On Sep 30, 2015, at 11:19 AM, marcin.krotkiewski <marcin.krotkiew...@gmail.com> wrote: > > Thank you, and Jeff, for clarification. > > Before I bother you all more without the need, I should probably say I was > hoping to use libfabric/OpenMPI on an InfiniBand cluster. Somehow now I feel > I have confused this altogether, so maybe I should go one step back:
No worries; happy to answer questions like this. libfabric is still fairly new, so there's not a lot of colloquial knowledge out there about it. > 1. libfabric is hardware independent, and does support Infiniband, right? In addition to everything Howard said: 1. One clarification: the Cisco usNIC support does not use InfiniBand (our product is based on Ethernet). 2. The IB support for libfabric, by definition, adds a little overhead compared to what you can get out of the raw Verbs API (because, at least as of today, libfabric is implemented on top of libibverbs). > 2. I read that OpenMPI provides interface to libfabric through btl/usnic and > mtl/ofi. can any of those use libfabric on Infiniband networks? The usnic BTL transport is specific to the Cisco usNIC solution. The OFI MTL can be used with any libfabric network that supports the libfabric tag matching interface. Today, that's the PSM and PSM2 libfabric providers. I think the MXM libfabric provider is still under development, but I think it's a goal for that provider to also support the libfabric tag matching interface. -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
