Commits
Chuck Lever committed a78868497c2
xprtrdma: Reduce max_frwr_depth 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 CX-3 Pro, FastLinq, and CX-5 devices. It reproducibly improves the throughput of large I/Os by several percent. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>