> Subject: Re: [Patch v8 12/12] RDMA/mana_ib: Add a driver for Microsoft > Azure Network Adapter > > On 10/21/2022 6:55 PM, Long Li wrote: > >>> The upper 8 bits of an ib_mr remote token are reserved for use as a > >>> rotating key, this allows a consumer to more safely reuse an ib_mr > >>> without having to overallocate large region pools. > >>> > >>> Tom. > >> > >> Right, my point was that one cannot encode INT_MAX different MR > >> identifiers into 32 - 8 = 24 bits. > >> > >> Best, > >> Bernard. > > > > The hardware exposes the number of MRs that exceeds UINT32_MAX. > > There is no software stack limit from hardware perspective. > > > > In this case, maybe it's a good idea to set it to 0xFFFFFF. I'm making the > change. > > Actually, 2^24 MRs is enormous in itself. Does this driver actually support that > many? Without falling over? > > Tom. The hardware can support that much. I don't see this driver will enforce other limitation on that.
