On Wed, May 08, 2019 at 08:07:59AM +0000, Bernard Metzler wrote: > >> >> Memory access keys and QP IDs are generated as random > >> >> numbers, since both are exposed to the application. > >> >> Since XArray is not designed for sparsely distributed > >> >> id ranges, I am still in favor of IDR for these two > >> >> resources. > > > >IDR and xarray have identical underlying storage so this is nonsense > > > >No new idr's or radix tree users will be accepted into rdma.... Use > >xarray > > > Sounds good to me! I just came across that introductory video from Matthew, > where he explicitly stated that xarray will be not very efficient if the > indices are not densely clustered. But maybe this is all far beyond the > 24bits of index space a memory key is in. So let me drop that IDR thing > completely, while handling randomized 24 bit memory keys. xarray/idr is a poor choice to store highly unclustered random data I'm not sure why this is a problem, shouldn't the driver be in control of mkey assignment? Just use xa_alloc_cyclic and it will be sufficiently clustered to be efficient. Jason
