On Fri, Dec 20, 2019 at 04:50:44PM +0100, Jack Wang wrote: > Hi all, > > here is V5 of the RTRS (former IBTRS) rdma transport library and the > corresponding RNBD (former IBNBD) rdma network block device. > > Main changes are the following: > 1. Fix the security problem pointed out by Jason > 2. Implement code-style/readability/API/etc suggestions by Bart van Assche > 3. Rename IBTRS and IBNBD to RTRS and RNBD accordingly > 4. Fileio mode support in rnbd-srv has been removed. > > The main functional change is a fix for the security problem pointed out by > Jason and discussed both on the mailing list and during the last LPC RDMA MC 2019. > On the server side we now invalidate in RTRS each rdma buffer before we hand it > over to RNBD server and in turn to the block layer. A new rkey is generated and > registered for the buffer after it returns back from the block layer and RNBD > server. The new rkey is sent back to the client along with the IO result. > The procedure is the default behaviour of the driver. This invalidation and > registration on each IO causes performance drop of up to 20%. A user of the > driver may choose to load the modules with this mechanism switched > off So, how does this compare now to nvme over fabrics? I recall there were questiosn why we needed yet another RDMA block transport? Jason
