On Mon, Dec 10, 2018 at 11:29:45AM -0500, Chuck Lever wrote: > Some devices advertise a large max_fast_reg_page_list_len > capability, but perform optimally when MRs are significantly smaller > than that depth -- probably when the MR itself is no larger than a > page. > > By default, the RDMA R/W core API uses max_sge_rd as the maximum > page depth for MRs. For some devices, the value of max_sge_rd is > 1, which is also not optimal. Thus, when max_sge_rd is larger than > 1, use that value. Otherwise use the value of the > max_fast_reg_page_list_len attribute. > > I've tested this with a couple of devices, and it reproducibly > improves the throughput of large I/Os by several percent. Can you list which devices for reference in the changelog?
