On Apr 14, 2011, at 12:37 PM, Brice Goglin wrote: > GPUDirect is only about using the same host buffer for DMA from/to both > the NIC and the GPU. Without GPUDirect, you have a host buffer for the > GPU and another one for IB (looks like some strange memory registration > problem to me...), and you have to memcpy between them in the middle . > > We're all confused with the name "GPUDirect" because we remember people > doing DMA directly between the NIC and a GPU or SCSI disk ten years ago. > GPUDirect doesn't go that far unfortunately :/
Correct. GPUDirect is a brilliant marketing name. Its name has nothing to do with what it really is: the ability to register the same buffer to both CUDA and OpenFabrics. As Brice says: GPUDirect does NOT send/receive data directly from the accelerator's memory. -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
