On Wed, Jul 17, 2019 at 8:09 AM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > On Tue, Jul 16, 2019 at 09:11:35PM +0300, Shamir Rabinovitch wrote: > > Following patch-set introduce the shared object feature. > > > > A shared object feature allows one process to create HW objects (currently > > PD and MR) so that a second process can import. > > That sounds like a major complication, so you'd better also explain > the use case very well. The main use case was that there is a server that has giant shared memory that is shared across many processes (lots of mtts). Each process needs the same memory registration (lots of mrs that register same memory). In such scenario, the HCA runs out of mtts. To solve this problem, an single memory registration is shared across all the process in that server saving hca mtts. Future expansion of this can be done on top of the new infrastructure to any HW object that is suitable for sharing (mainly those that are not saving important data in the user context).
